I have been told that MacBooks don’t have the “ALT” key

Correct. Almost all apps use the “option” key on a Mac, which is not a key on Windows keyboards. It more or less is just a change in the key name for most apps. I just tried using it in Excel to create a new line in a cell, and it has the same behavior as the ALT key on a Windows device.

As well as a software called Power Bi doesn’t work well on MacBooks (slow, freezing or straight up not working). My friend had this issue in university and was forced to use my laptop to do the models.

Third-party software compatibility is obviously going to be an issue for some software on MacOS.