I can't get it! Maybe you have some help.
I have integrated a few MacBooks into Jamf and I can manage them without any problems. Now I want to integrate the rest of them into Jamf without using self service or policies. Does anyone have an idea and a precise procedure?
And can I activate Self Service afterwards? After I have configured everything?
Your question is unclear. To enroll machines in Jamf you can use one of three ways - manually (like going to your server's built-in enrollment webpage or with a package created by Jamf Recon), remotely with Jamf Recon (have to have ssh enabled on the machines and know an admin login to the machines), or automatically with Apple's Device Enrollment Program and Business Manager web sites (requires the machines be enrolled in DEP by reseller). In almost all cases a policy will have to be installed on the machines so that the machines can be effectively controlled by Jamf. This is due to the security changes Apple has implemented. Self Service gets installed on enrollment, but you don't need to use it or have any policies show up in it.
You cannot effectively manage a machine these days without the MDM Profile from your Jamf server being installed and approved on the machine.