Am i confused about the roles of the game?

In most of my games i find myself arguing with other people about what we/they should be doing ive droped down to low guardian from high crusader most likley because of cavern craw,l but even before that i just found that im not having much fun in the game outside of collecting outfits.

Maybe its just me but i feel like dota is much like basketball or soccer. Theres a flow or motion to the game and if you follow it you should have a good chance at winning.

However in most of my games it feels like im playing basketball 2 people are playing tic tac toe in the corner. one person is eating glue and the last person is loosing a match of arm wrestling against his own shadow. But maybe its me.. Maybe im the glue eater and everyone else is doing just fine.

I know just like any other sports there are plays to be made but these usually follow a basic understanding of the flow

This is my current knowledge of each role (when played ideally)

Hard support: Main ward purchaser (atleast. 2/3 of the wards), lane puller, creep denier harass/ distract and stack camps. If the lane goes well leave at about 8-9 minutes stacking along the way to offlane to help push tower if not or if the enemy keeps coming back to feed your carry stick around and help where you can/ continue to stack.
After the laning phase continue to stack camps stay close to your offlane or mid as you attempt to take enemy ground but dont neglect warding to keep your current farmer safe.
Your items should be a survival item preferably glimmer due to the ability to toss it on others to save them after a bad fight or when you anticipate a magical nuke to soak up some of the damage/ euls to keep your cary safe till bkb duration runs out/ force staff to protect from enemy ranged carries and all around bad situations. Followed by whatever disable item fits best on your hero/situation sometimes even if its counter intuitive. Ive turned a game around as CM by buying HH to shut down the enemy carry turned a loss into a win. This is outside of normal circumstances as your offlane or support should be buying this item. You have the least amount of farm priority highest priority on exp books.

Support: my second least knowledgeable position. basically you're the lane guardian. buy wards (roughly 1/3) stick in lane till level 4 or 5 harassing pulling and blocking camps. Move to help mid around this time unless theyre moving to genk. at this time stack ancients on your way over and on your way back and at any time your offlane has the lane pulled to tower. Be ready at all times to travel to safelane make sure you have atleast 2 teleport scrolls on you at all times if youre not spiritbreaker/np/underlord in case the lane gets overwhelmed. Or to help stop a genk.
After the laning phase you should be with mid or offlane/ hard support pushing into enemy territory doing whatever you can to stop the enemy farm.
Your items are similar to hard support. First item should be some sort of disable or detriment to enemy stats then you can move on to damage items. Or auras if youre an aura support like sb/ underlord or undying.
Second to last priority on farm second priority on exp books.

Mid: the only position i don play yet.
Probably genk around level 6 your farm should ideally come from/ kills pushing the wave / farming neutrals on the side when prepping to genk whoever comes to stop your offlane entourage's push. Second highest damage dealer. second most important farm priority second to last prio on exp books.

Offlane. Tank/pusher
Your job is to be there. In a fight you should be there. In a push you should be there, normally the initiator of fights the pusher of waves the usher of chaos. Eat the enemy then their jungle and their towers. Your farm priority is the enemies farm. In the laning phase deny deny deny i almost think its more important to deny as offlane than it is to get your own last hits. pull that wave to your tower. Make them over extend perfect for you or your mid to snatch them up and make a kill. 90% of offlanes can take the creepwave close enough to tower without sacrificing farm to tower blasts or adding damage to the tower once you get an hp regen ring which i suggest grabbing even before boots on most heros.
Once that laning phase ends stop denying and ram your forces down the enemy throat. Push till they come for you then move to another lane till you have all tier one towers making each lane safe to farm while robbing your enemy of space. Both supports should follow you in this endeavor do not push without one or you risk feeding. Your items are sustain. Be it bkb or oct core blademail whatever is nessicary on your hero. On certain heros you shouldnt worry about kills or deaths as much. as you should be the first down in team fights kills are nice but if you only get assists as long as youre giving your cores time to do their damage and win thats all that matters. You have 3rd pro on farm and last prio on exp books unless you really failed in the laning phase.

Safelane: the goalie/goal.

Youre the big bad. You are the deciding factor you are the one the enemy should be scared of and preparing for. your goal is to farm.. Farm like its nobodies business just keep farming
once the laning phase ends and your offlane comes move into your jungle and farm. Then you hide and you stay hidden till your ult is up or you have nessicary items whatever they are for your hero. Learn to deny better than the offlane pull the wave to your tower but not close enough to be overwhelmed. While you farm stay close to your team, never let them be without backup. If a fight breaks out you should jump in last and clean it up. Do whatever you can to stop them from taking towers or objectives. You are the last line of defense between your ancient and the enemy and the first line of attack against theirs. overall your life is more important than a tier 3 tower after that you should be doing what you can even dying to stop a heavy push.
On the offensive the opposite is true. If the push takes your life it probably wasnt worth it.

I didnt talk about rosh here as he is a side objective and hero priority is different for each game.. But i feel like i have the jist of the basics of game flow. Feel free to correct me if im wrong.

I know there are certain aspects on offlane that change per hero but i think theyre situational and especially for early ranks theyre not ideal. Like phoenix offlane or ogre magi etc.