Returning player from 2017

Hi guys,

Just fired up Elite Dangerous yesterday, plugged in the HOTAS, did the tutorials and jumped back in to my save from 2017.
I have a cobra mk3, normally equipped I would say.
600k credits

I am at "dealer" level for trade it appears.

What should I do from there ? Is there a website that recaps everything that is happening in the Galaxy ?

I remember profitable trade routes, are these still the best way to make money? Is there a website to track them ?

I heard about the war, is it still going ? Am I supposed to do something? Is there an area to avoid ?

Should I buy Odyssey extension or can I still play "legacy" without missing too much ?

What's the next ship I should be targeting? Should I grind for something specific right now to make my life easier ?

Sorry a lot of questions, and many more but it is a bit overwhelming to come back to such a game (space life experience).

Thanks !