Why am I so bad at this game?

This is my first time playing a game with this fight/play style. I have watched some videos on tips and tricks for new players but I don’t even know where to begin. I’m currently using shadowheart , astarion , karlach and myself who is a sorcerer, we are all currently level 4 and I persistently die in whatever battle I try next. The main issue with this is shadowheart doesn’t really help heal my team and karlach will miss most attacks. It’s disheartening because I want to like this game and get through the story but even with a balanced difficulty it is hard to get through simple fights. I’m currently reuniting with Lae’zel after falling off the ship and finding her with a bunch of other warriors with a dragon.

I’m not sure if this is a skill issue on my part or what

Edit: Thank you everyone for all the advice! I hope to use some of it to get better, i previously have played games like God of War and Red Dead so this is a completely different thing.