UK and US marketplace

I’ve opened an Amazon Seller account and signed up for FBA, but my account seems to have been opened with the US marketplace and the UK is not showing anywhere as an option to add. I’ve got Japan, Canada and US but no option for Europe or UK..

Have I signed up on the wrong platform and I need to start from the beginning?

Or should these be showing as optional additional marketplaces and there is something wrong with my account?

If I do need to make a new account I really cba going through the verification palaver again, so would it be a bad idea to be a UK based seller selling to the US? I just want to get going with it 😅

TIA