On PC the remaster no question. It'll have the most active playerbase with a few quality of life changes that you'll wish you had (like crushing stacks of souls).
As for playing Dark Souls 1 or 3, it's up to you. Mechanically 3 will be more familiar, while 1 will feel clunkier and more dated but in my opinion has a certain charm that the later games miss.
I don't mind paying for services I use to avoid my data being the payment (like Kagi or Protonmail).
But I don't like the idea of paying Google AND having my data farmed.