For others to be able to play your game online, you need to publish it since pygbag is not ( and should not be) reachable from outside your local network. Itch.io allows you to do that and more.
To upload you website to itch.io you would need to zip its source code and upload it to itch.io
Use python3 -m pygbag --archive the/game/folder/main.py
and get the web.zip from ./build/web.zip in the game folder
or :
To set up the project:
This file will be played in the browser
After following these step, if you view your game page and set it to public, then you would be able to see your game.
Thought, if your are unable to do so, you can ask for help in the pygame discord server