I've not played the other fromsoft games, only Sekiro. But from what I've heard - unlearn everything, mainly dodging. Dodging has its place, as does jumping, but for a fair while try to force yourself to only parry. Fight every enemy, learn the how to fight fast and how to fight slow, just parrying and striking. Find the rhythm.
Anyone I've seen saying it's the hardest fromsoft game generally dodges and moves around a lot, and makes the fights way longer than they need to be. I went in with no fromsoft experience (except a bit of bloodborne from a aaages that I have forgotten) and found it OK. Hard as hell to be fair, but it's not my usual type of game and it always felt doable with enough practice. So, treat it like it's own thing and be prepared to learn a new fighting style, and you'll be fine!