techsupport and homenetworking

Two subreddits I used to be very active in were for techsupport and networking/home networking. Anyone know if there’s Lemmy communities for the same?

Also, related, is there a way to list communities available from a specific instance? Like if I wanted to see all communities local to Lemmy.world or something (that’s not my local instance), can I do that? If so, how?

I’m still getting used to the fediverse way of doing things, I love it here, I’m just having trouble getting myself up to speed relative to all that I was subscribed to on Reddit.

TIA