First before saying anythings i would like to share my Point of view that the Interpretation of what a GodForm is may vary from a Magician to another, Being a Strong Believer in the Subjectivity of reality.
So here my answer to your Question
1-What is a GodForm :
For me a GodForm(A Personal One) is your GodSelf that come after your HigherSelf or HGA or Daemon etc… This Part of yourself is even more Powerful then your Higherself, it is a Part of yourself yet a Individual Entity. This entity is often connected to specific Kind of Magick such as Healing, Cursing etc… or Certain Magickal Discipline such as Vampirism, Astral Working , Shamanism etc… And those Connection most of the time reflect the True Will of the Magician.
2-What is the Difference between a Godform , the samsaric Self etc…
For me the Difference is that the GodForm is a Part Higher(More Developped) then the Higher Self and the Samsaric Self.
3-Can a Person have more then one GodForm or none
A Person can definitly have more then one GodForm, in Fact even the GodForm have a HigherSelf, then a GodForm and it go on and on, eternally. I dont think people can have no Godform, they most probably can never meet and Merge with it in many Life time but i think that ultimately, a Meeting and a Reunion will Happen.
4-What does the Merging with your GodForm
I believe this answer will Change from Person to Person, but for me, my Merging with my GodForm provided me a Greater Acces to More ''Esoteric Knowledge, a strong Boost in my Own Personal Power, an Great Increase in my Capcity such as Soul Travel, Healing and Also a greater facililty to teach. among other things.
It is hard to Describe it in Words since it is what i call an Experience you must have by yourself to fully Understand, it is like describing what being burned by Fire to someone Feel, you can describe it as much as you want, a Person have to actually experienced it to really Understand it
6-Can it affects the process of Death and the After Life
I think so but since i’m not dead yet i can’t confirm
7-How to Merge :
Personally Merging with my GodForm was a Step i was Ready for and During the Part of my Angelic Pathworking where i needed to Evoke the Archangel Raziel, i was Directly guided to a Another Magician that Helped me along the Process. (Arcane) The Process can vary from person to Person but here how i did it :
1-Meet your GodForm in a Shamanic Core Journeying and receive instruction from him about the Merging
2-Meet your GodForm astrally and receive Instruction from him about the Merging
3-Evoke your GodForm essence (Not a Full Physical Manifestation)
4-Evoke it Physicly
5-Receive a Sigil of your GodForm and Charge it and create a Strong Connection with it
6-Invoke your GodForm
7-Be Possessed by your GodForm
8-Merge with it (The Merging process is hardly descriptible in words)
9-Let him settle for a couple of day or weeks, then Construct another Sigil with the Guidance of your GodForm and use it as a Power Object and as one of your Personal Symbol of Power.
8-How do you find your GodForm :
I think it Happen when your ready to do so
9-What the Relationship looks Like
If you have ever been Possessed by an Entity Fully (The Actual Merging) it is very Similar, the Entity and you are one but two at the same time, You always feel its Energy and essence in you, You can Take its Form(Astrally) and use its Power etc…
10- What GodForms is the most prevalent?
Each Human have a Different GodForm so none imo
I hope this answered your Question!
Best regards!