@KayBains
My understanding is that there is no direct way to share a Flow with all users. If you have an Org Wide Team, you might try adding that group as an owner as all users are automatically added. Please note that unless you can add the users as Run only users (for a selected item flows, button Flows) that your users will be able to edit the Flow - probably not a great idea.
Can you provide some details on your use case?
If your goal is simply to make the Flow available for everyone to use, consider exporting the Flow as a package and putting that package in a place where everyone can access it and then import it.