From your Mastodon account, just search @technology@lemmy.ml. You’ll see the whole community as if it was one user. You can also interact with comments, reply, or upvote.

Note that Lemmy kind of does a bad job of integrating with Mastodon. Each community is an account that “boosts” (retweets) every post and comment in it, making it very noisy. I talked to the devs about it a while back and better integration is just not something they’re interested in.

Kbin (which is a Reddit clone like Lemmy) works much much better. If you search @Disneyland@kbin.social from Mastodon, you’ll see the Disneyland magazine appears to be an actual user and the threads/comment sections work like you’d expect them to on Mastodon. Any posts appear to come from that Mastodon account (instead of being “boosts”).

Kbin allows you to follow Mastodon users as well, which Lemmy doesn’t support and has no plans to support. You can flip between “Reddit mode” (“Threads”) and “Twitter mode” (“Microblog”) at the top of the page on Kbin, effectively merging 2 services into 1.

Kbin’s roadmap also has it integrating more ActivityPub stuff natively over time. It’s the reason why I use it over Lemmy.