User login limit in Netskope client.

I am assuming you meant login to the Netskope UI.

There is not a "limit" persey. However, you can disable concurrent logins by the same admin if you chose.

https://docs.netskope.com/en/disallow-concurrent-logins-by-an-admin.html

No, I didn't meant login to Netskope UI.

I mean that, From one User Id, how many logins possible to Netskope Client.

how many devices can be onboarded from one user?

There is no limit.

The license is per person, not per device.

So, you can have multiple people log into one device, and each person could be part of a different group that gets a different browsing policy, or you could have one person log into multiple computers, and that person will receive the same policy.