
Hi @mperez84 ,
Do you want to make user could only create sharepoint custom form, but could not create powerapps app?
1)the permission of creating sharepoint custom form
You need to make the user has the license of Office 365 plan that includes Power Apps.
2)the permission of not creating powerapps app
You just need to assign this user the security role that does not has the permission of creating powerapps app.
You need to assign roles in one by one environment.
//only the admin of the environment could assign security role
Security role is environment level.
You could assign Security role here:
https://admin.powerplatform.microsoft.com/
Here's a doc about this for your reference:
https://docs.microsoft.com/en-us/power-platform/admin/database-security
Best regards,