If you want to restrict to access your Magento Admin, then configured with specific permissions. Magento has option to create permissions. Add user with a different name and password, then create a roles and assign a roles to each. User will able to access only assigned roles. In Magento, Administrator role assigned to User By default.How to manage Permissions by creating Users and Roles ?
Step 1. Creation of Roles: Go to Admin -> System -> Permissions -> Roles
How-to-set-Permission-and-Roles-in-Magento-2Click on Add New Role

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Step 2. Complete Role Information

  • Role Name: Enter name of role.

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Step 3. Assign Resources

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  • Resource Access: By default it is Custom.
  • Resources: Mark the resources that you want to assign to Role.

After that click on Save Role
Step 4. Create Users and assign Roles
Admin -> System -> Permissions -> Users

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  • Click on Add New User

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Step 5. A. Complete User Account Information

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  • User name: Name of user.
  • First Name/Last name: Enter the name and last name for your user.
  • Email and Password: Enter Email and password.
  • Set This account is Active to create user

B. Assign Role to User

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  • User is created with Roles

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Step 6. Now Log in by using newly created User and Password

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  • User can access only those roles that assigned to him.

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