Em....... Hi.
I'm not from Scotland, not even from Europe. I want to live in Scotland in future. And I have a T1D.
Is there anybody who had moving experience with this disease?
< Sorry for my English. It's not my native language. >
Personally, I think you'll probably have more trouble entering and staying in the UK rather than dealing with T1 once here. (NB, not a T1 myself but I do know a little about the health service in the UK and right to remain etc).
Anyone who is lawfully and permanently in the UK (Scotland is part of the UK) has full access to the NHS, including registration with a GP, referral to secondary services, prescriptions etc. So you would receive standard NHS treatment for T1.
Permanently is easy - it means, in practice, an intent to stay for at least six months. You don't have to wait six months: if you arrive (lawfully) and you intend to stay longer then you'll be OK on that factor.
The question for you is whether you already have or can establish a lawful right to remain. There are a number of ways to do this, and without knowing anything about your circumstances I've no idea whether you'd meet the criteria as they're currently being applied.