Hi @ManojAhuja ,
Firstly, licensing is a field of study all on its own - so disclaimer first, this is just an opinion which may differ from reality - I'm no licensing specialist.
That said, you can make use of Power Apps Portals to create customer facing apps. The authentication method you choose for your portal will determine how you manage customer identities.
For someone to make use of a canvas PowerApp, well let's just say that the Power Platform is for the most part internally facing - it is not natively designed to share with outside parties, with the exception of portals mentioned above.
To use a canvas app, the user needs to have an account in your AD - whether this is a localised account or guest account will probably depend on your security team.
They then also need to have an enterprise license that allows them to use PowerApps.
"Enterprise" licensing typically excludes the use of personal email domains like gmail.com - so it's unlikely he would be able to authenticate with your app using his gmail credentials.
You might be able to surface the app up in Teams and add him to the Team as an external user, after his account has been provisioned on your AD as an external user - however you would need to make sure the external user has access to the app and its data sources and no guarantees it will even work - there are way too many moving parts to predict how successful this would be.
A lot of "ifs mights and maybes", but like I said, it's not natively focused on external user participation - your best bet is to look at portals.
Kind regards,
RT
