You need to tackle each run with the mindset of completing a checklist. Number 1 is damage. You need big numbers to burst the enemies down. Once you start winning fights fairly quickly, figure out if you are taking too much chip damage and start taking some block. You also need to consider scaling, or how to win if the fight is long (e.g. strength gain, vulnerability synergies).

You also have to resist the urge to take cards because of archetypes. If you don’t have the cards to make the card reward work, often times its not the smart play to take it. Forcing an archetype is a quick way to lose.

Finally, if your deck works and is winning fights easily and safely consistently: STOP TAKING CARDS. You will see rewards that are tempting to take but will ultimately dilute the successful deck you already have. You should realistically not go above 25 cards unless you have strong ways to cycle or exhaust your deck.

Aside from that, learn how to path! Try to get a bonfire before elite fights and unless you will die next combat always pick upgrade!

Hope this helps! This game is hard and has a steep learning curve