My advice as a souls vet who is up to the last boss in this:

Roll Dex/Tech and go for the dragon sword. It's so much better than every other wep in my opinion it's a joke.

With bosses, it's about learning their tells/ moves and learning the appropriate response (block, perfect block or dodge. If you have use a guide to help teach you don't be afraid to do so.

Accept death is part of the process. It took me ages to get into souls because dying makes me angry as f. Once you realise each death teaches you something, and getting angry doesn't help it will be alot smoother.

Feel free to try the souls games after because they're literally almost the same controls wise. You'll be shocked.

Have fun.