You will get excellent care for your Type 1 Diabetes on the NHS , but be prepared that it may not always be the 'latest and greatest' and some of that is postcode lottery.
Do you use a pump?
If you're already on a pump, you'll probably have better luck convincing your health trust to continue supplying infusion sets, cartridges, etc then later on if you decide you want to use a pump as there will be certain criteria they want you to meet. However!, the most common pumps are Medtronic ones, so if you use an Animas, a T-Slim,an Omnipod, etc you may have trouble getting these supplies. It also hugely depends on if that particular area pays for those particular pump supplies and likewise, depends on if the Diabetes Specialists are familiar with that type of pump and 'support it'.
If you don't pump, do you use pens? Pens are much more common over here than syringes and vials, though you can probably continue to use a syringe if that's the case.
Do you have a CGM? Be prepared to pay out of pocket for the sensors if you do.
Glucacon will most definitely be available, though spare kits may require a fight on your hands.
Novolog is called NovoRapid here. Humalog is the same. I am not sure if you can get Apidra anymore.
You can get Lantus, Levemir and Tresiba here. Don't think Afrezza ever made it over here.
What meter/system kit do you use? Certain health boards will only pay for a particular type of kit. And you very well may have a fight on your hands if you want to test more than 4-6 times a day.
You should be able to get ketone meters no problem.
Also, all numbers are in mmol/L here instead of mg/dl and HbA1c is also reported in mmol/L instead of %. (So if your meter breaks and you have to get a replacement, you'll get one in mmol/L which will read example wise: 9.6 mmol/L instead of 173 mg/dl) So that may mess with you a wee bit at first.
You will most definitely get routine blood work like HbA1c every 3 months, eye exams, feet checks, kidney, heart, and neuropathy checks as well as routine. You should also get a free flu jab.
Type 1 is managed usually by Diabetes Specialists Doctors and Nurses, though your GP is often in the loop too.