jointhefediverse.net seems to be a commonly linked resource for directing people to join the Fediverse.
Curiously, it does not list Lemmy under the list of Reddit alternatives. Their GitHub README explains why.
Previous relevant discussion: https://lemmy.ml/post/78808
Well, horrible genocide apology takes, TBF. I didn’t mean to downplay the gravity of the points they bring up in the archived mastodon thread.