I used my level 40 boost! Right or wrong thing to do?

So I bought the battle pass bundle got a level 40 boost and used it I was only level 19

I’m not a huge ‘oh I need to know the story to the game’ kind of guy.

But I’ve missed a lot I know.

So what’s my new main goal now guys?

Where should I be farming for better gear also?

Thanks comrades.