I am not someone who follows/has interest in Geo-politics. In lemmy homepage majority of posts are political. Those lemmy’s I do not expect to have political posts in them like c/technology, c/memes, c/lemmyshitposts, their top posts are related to politics. My subscribed, local, and all is full of it. Is there a way to filter them out?

Does this mean I only see comments from the instance I set up an account with?
Nah, you see comments from most instances, since Lemmy.ml federates with most instances. A user from .world can’t see my comment, as an example, since their instance defederated mine.
No, comments are federated, or else I would be almost an island by my self on my instance