Can several computers share one program's data?

Keep the data locally on the computer if the program runs on one machine and you want it to work with no internet, accepting that backups are your job. Choose the cloud if several computers or branches need to see the same records at the same moment, and you accept that work requires an internet connection and a sign-in. The deciding question is how many computers need the data.

Copy the installer to the second computer on a USB drive, or download it from your account, then run it and follow the same steps you used on the first machine. Check first that the computer runs a supported Windows version. Note that the installer moves the program only, not locally stored data. To move data you need a backup that you restore there, or a shared cloud database.

Permissions are given through roles, not individuals: you define a few roles such as owner, manager and staff, decide for each role what it can see, add, edit and delete, then assign every employee to a role with their own sign-in. An Excel file cannot do this reliably, which is why you need a system with sign-in and a database.

A program works offline when two things are true: it is installed on the computer itself rather than opened in a browser, and its data is stored in a local database on that machine. Then it opens, sells and prints even if the connection is down for days. The trade-off is that the data stays on that one computer, and backing it up is your own responsibility.