Elden Ring v Dark Souls difficulty?

First time Dark Soul player here! I tried some games earlier like DS1 Remastered and DS2 but I did not find them very enjoying. But playing Elden Ring changed me maybe because it is so much of an open world that I can immerse myself in it entirely. But Elden Ring feels tough for me. So how much of DS are tougher or easier? My friend told me that ER is the easiest of them all.