How to add more custom permissions in nopCommerce?

Hi there,
I'm using the nopCommerce 4.40.3. In Admin/Security/Permission there are lots of different permissions which can be assigned to couple of roles. I want to add more custom permissions myself. how should I change the code behind? Actually, I'm newbie to nopCommerce and not familiar with it completely.

Create a new Permssion

        PermissionRecord superviseSystem = new PermissionRecord
        {
            Name = "Admin area. System Supervisor",
            SystemName = "ManageSystemSupervisor",
            Category = "Your System"
        };
        await _permissionRecordRepository.InsertAsync(superviseSystem);

Check if the current user has access

                return await _permissionService.AuthorizeAsync(superviseSystem);

thank you very much.