Hi, im running pulv druid, is it possible to be lvl 100 before end of season? Im lvl 53

Depends on your playtime.

Heard that level 85 is the same amount of exp you need for the last 15 levels.
It's possible to make 1 level per hour until level 100 if you farm nm dungeons efficient. In group and with the latest xp buffs should be even faster.

I only kept the items with the most upgrade potential for my gear and could run ~3 dungeons in a row before going to town and sell/salvage.
This is for level 75+ when you have your final gear and only make minor improvements.

For selling always go to tree of whispers wp because blacksmith, vendor and chest are closest to the waypoint there.

Check out dungeon tier list on maxroll to run s and a tier dungeons. Aim for monsters to be 10 levels higher than you for the max xp bonus.
I think in t4 monster lvl = sigil lvl + 54

Happy grinding

8-10 hours a day you will get it way before the 17th

easy i did semi-casually ~1 month 1-100 but I knew what i was doing. and in terms of some other people, my semi casual is their hardcore mode. daily avg prolly 2-3h (some days off, weekends more hours etc)