First steps with NHI

I apologize for the layman question, but I tried to do a search and got confused with all the info I read here.
I got the NHI card a while back and I would like to do a physical check (blood tests etc.). Where do I go to do that? and in general, how does the system work here? from what I have read online I have the impression people just go to the hospitals/specialists as they please. Back home I signed up at a GP’s clinic and any problem I had I went to see them first. they would give me a letter to see a specialist if necessary.
is it the same here? do I need to go first to a GP and he sends me to specialists? where do I find a GP? in the hospital?
Any help will be appreciated.

In general, if you need to see a doctor go to the hospital and tell the people at the registration desk roughly what’s wrong with you. They’ll then send you to the relevant doctor - eg if you have a sore throat, they’ll send you to an ENT doctor. In my experience, doctors in hospitals that they send you to will all speak English.

NB That doesn’t mean all doctors speak English, only that the registration people will send you to an English-speaking one.