Yes, at least for now, there are 2 different PowerShell apps out there and both can run on the same computer. I envision Microsoft will slowly remove Windows PowerShell from shipping with Windows by default in the future. It may be replaced by PowerShell or by nothing, leaving it to user’s discretion whether she/he wants to install it manually or not.

There are some differences, modules, cmdlets changes between the two apps. There is a pretty good/complete article that details all the changes, differences etc. Check it out here:

Differences between Windows PowerShell 5.1 and PowerShell 7.x