New player, advice

I’m coming into this game completely blind and with no extraction shooter experience whatsoever. I’ve played a few games now and seem to achieve very little, only one successful extraction and that with a bag full of what I can only assume is semi-useless junk.

What should I actually be aiming to achieve at this early stage? Just explore around picking up whatever loot I can find then extract with whatever I’ve got? Do I aim for the marked Medium/High loot areas or just loot in the unmarked areas?

Most players seem hostile so far, which is perfectly fine but does this mean I should play quite slow and avoid areas where I can hear action going on?

Some direction would be appreciated, thanks.