How to restrict access SSHD access to user@ only and deny all

Is there a way to restrict only one user to ssh into a machine

say for instance i want to all all users to ssh to this hosts, but only allow user1 to ssh to this hosts from hostB

something like user1@* deny but user1@ allow and any other user allow access via ssh ?

yes, AllowUsers and DenyUsers. The allow/deny users directives are processed in the following order:

DenyUsers user@host
AllowUsers user@host

In other words, the following is all you need

DenyUsers user1@

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