Q How many types of intergrated headsets

Just trying to work out what headset I’ll need for a Dolan CX frame.
I’ve seen them described as ITS, Intergrated, 45/45 and 36/45.
From what I can tell the intergrated forks are universal, but the actual frames differ as to what headset they take. Is that correct.

I’ve actually got an unused FSA intergrated 36/45 at home?