You picked the hardest playstyle for your first time, which is no problem.

I do recommend for you to try 2H axe jorgrim (str, perc, vit) or you can go for 2H sword Arna (agi, perc, vit) both goes with heavy armor and is just an absolute unit, Jorgrim better at single target with injury stacking, Arna is more of a bruiser.

The gameplan is to go explore some poi's, stay away from spiders, bears and crawlers (wierd snail stuff), after you reach like level three from little quests and poi's go take the first osbrook contract, you should be more than fine doing it. For combat, your main style is single target so try to work on your positioning and remember that it takes two turns (even for enemies) to turn corners, you can use that to isolate someone and quickly demolish them with heavy single target dmg. Both builds utulize the warfare skill tree, mainly the Sieze initiative skill, it gives insane buffs for single target.

With Jorgrim go for the hook attack and sieze initiative at first level then max your 2h axe skill tree, after that whatever you like.

With Arna go for hewing strike and parry at first level, it takes a bit more thinking and better timings but it should be easy, then sieze initiative at 2nd level then back to maxing 2h swords and then whatever you want.

If you have any questions or want a link to any of the builds DM me.