If you want to share something with just some people, they can create a Tailscale account and you can share it with them that way.

For public access, accessing it using a domain that uses your public IP should work. Most routers let you do that (“hairpin NAT”). Although to be honest, most of my public facing things are on a VPS rather than on my home server. More reliable and a higher quality internet connection for a fairly cheap price per month.