2 computers

Here is the Adobe page that gives the information on installing Adobe applications on multiple computers, including how to deactivate one if it is no longer necessary and accessible.

https://helpx.adobe.com/ca/download-install/using/install-apps-number-of-computers.html 

Yes, if they are for your own personal use, not at the same time.

No, not to share with friends, family, staff, colleagues or students.