You can find more information about VDMOStool from this post
Howto .model without the .model? - QSPICE - Qorvo Tech Forum
Here is a device guideline demonstrate some critical MOSFET parameters and their effect by referring to Qspice help and also Giuseppe and Paolo textbook
Qspice/Guideline/Qspice - Device Reference Guide by KSKelvin.pdf at main · KSKelvin-Github/Qspice