By setting Account Manager restrictions, users can then only access records they're the Account Manager of.
You'll need CRM Admin rights in order to follow the steps in this article
Step 1: Go to Settings Centre
Navigate to the Settings Centre by clicking on the cog icon in the bottom left-hand corner of the CRM. Once within the Settings Centre, search for 'Configure User' in the search bar then click on the 'Click to Configure' link.
Step 2: Choose User
Simply choose the CRM user that you wish to set Account Manager restrictions for by clicking on the associated pencil icon.
Step 3: Enabling Account Manager Restrictions
Once within the CRM user's settings, navigate to the 'Permissions' page and click 'Enable' for the Account Manager restrictions.