I am wondering how to preinstall windows on a computer and activate the first boot screen without the Windows OEM Preinstallation Kit
Download and install the WAIK use the "Windows System Image Manager" to create an answer file that is to your liking and include the option in the "oobeSystem" section for "Windows-Deployment" to "Reseal" in "Audit" mode. Place that answer file on a USB name it AutoUnattend.xml and install the OS with the USB plugged in. The system should boot to the Administrator user... you can tweak the system update it, add software etc.
Here is a Step-by-Step guide
Then run the Sysprep utility with OOBE selected not Audit. You should select Shutdown for the shutdown option as well. On the next boot you will be presented with the OOBE(Out-Of-Box Experience).