LNAT on UCAS - HELP

I was looking for the center I am going to take my LNAT test in, couldn't find it so added it to my UCAS form manually. Now, I don't know how to find the center number....

You don’t need a centre number. It’s only required for centres that are in the ucas systems

so next to the centre at which I am taking the exam, I can leave the 'centre number' blank?

If the centre wasn't on the UCAS list then the centre doesn't have a number. Only exam centres on the UCAS list will have a centre number.
"If the centre does not have a number, leave this box blank." (UCAS help text from clicking the ? next to the centre number box)

It's just that the booklet our school gave, with instructions on how to fill the form, next to the same centre, they have put a centre number, which confuses me because I couldn't even find the centre on UCAS. might call them today to check because I am anxious that my results won't go to the universities

For LNAT it really doesn't matter. The mapping to UCAS exam centres isn't how the results are sent to universities.

so it doesn't matter if I fill in the Admissions test bit onto education section? I am going to anyways, but just checking..

for LNAT the Centre NUMBER doesn’t matter.
You MUST list all qualifications including lnat in your application.