If I'm not mistaken to make your instance available to other people you'd have to set up a reverse proxy. And a correctly set up reverse proxy shouldn't reveal your IP, only the local IP (127.0.0.1).
I might be wrong, so ask on the [email protected], since it's more active than this community.
However renting a VPS and hosting your Lemmy instance there is probably a better idea if you plan on creating a community, since it will minimize risks (DMCA notices, bugs in the Lemmy source code that could expose your server, etc). And it would make scaling easier if your instance grows.