You can create a team in CRM and assign users to it to restrict which records they can see.
Go to the Admin page.
Click Team Management.
Click the drop-down next to the module name.
Click Create Team.
Enter a Name and Description.
Click Save.
Click the new team name.
Click Select to add users to the team.
Click Save.
The basic principle is: a user can only see a record if they belong to a team assigned to that record. Admin users are exempt from this rule. For example, imagine you have two accounts: Account A (assigned to the Midlands and Sales teams) and Account B (assigned to the North East and Sales teams). A user in the Sales team only can see both accounts. A user in the Midlands team only can see Account A. A user in the North East team only can see Account B. You can also add a user to multiple teams — a user in both North East and Midlands would be able to see both accounts.