Assuming you have create a IPSec VPN on Paloalto Firewall, these are the steps to create VPN group and users.
- To create VPN group, go to Device>Local User Database, click Add to create VPN Users group.

Navigate to Device>Authentication Profiles, click Add. Enter the Name, select Type, and Username Modifier to create the Profile.

Click Advanced, and then click Add to add group you create at 1.
2. To create and add a user to the VPN group, go to Device>Local User Database, click Users and then Add.

Now, go back to the VPN group to add the user you just created.

3. Save all configuration and test it.