“Full name”

I made an account on college board a few months back and my name is something like:
ABC DEF GHI JKL
in my passport, so when they asked for first and last name i wrote ABC JKL. No middle names, it’s:
My name, fathers name, grandfathers name, great grandfathers name

So i wrote mine and my great grandads.

My question is. Is this the same account ill be using on my exam date?? Or does the centre make me a new account. + will this affect my univeristy application when i send my results? Will they be able to match my name if i later write ABC DEF in my college application.

Or are we told to write our name again when submitting grades to the univeristy through collegeboard?