Lemmy isn’t one service like Reddit. It’s a piece of software where anybody can run their own lemmy instance. Lemmy.world is the most popular, but there are many others. And those choosing to run an instance can “federate” with other instances, which means as a user you can see posts and comments from the other instance even though you are logged into the one you have an account on.
So the commenter is recommending you look at posts or comments from users on other instances that have more stringent sign up policies, and migrate your account there. Since your account is new, you likely don’t need to spend the effort on migrating your account and instead can just set up an account on another instance/server.
But it’s also fine to stay on lemmy.world. Just be respectful, voice your opinions like you would in person with other humans, and you’ll be fine. And if you’re just here for the memes, that’s ok too! Enjoy them! And welcome to lemmy.