If you want to exclude some specific computers from MFA from all users, then you can set the "IP Filter" in the Computer Logon Agent policy:
You can specify a single IP or a range of IP addresses. All computers in the IP Filter list will be excluded from MFA.
Please note that the IP Filter rule in the Computer Logon Agent policy is global. It applies to all users.
If you want to exclude some computers by their IP address when they are used by some specific users, then you must set the IP Filter option in the Logon Policy that is applied to the specific user or user group:
