Type 1 diabetic from UK studying in re USA - medical cover

Not the USA but when studying in Europe (6 months and ~10 months iirc) I would get my GP (under duress in some cases) to prescribe a job lot of "things" to cover 6 months and then take it with me. I was closer to home and did come back so I was able to put a repeat in remotely (which was not the done thing back then) and pick up a resupply to take back with me.

Perhaps there are better methods with reciprocal agreements to source supplies locally, etc., but if not it might be worth looking at something similar to the above and ensuring the GP in question is on board with the whole thing (there's no reason for them not to be afaict, but it is outside of the norm so may need a conversation.)

No, I didn't get any insurance, at least not that I remember doing - afaicr there were either reciprocal agreements with the NHS at that point or the up front costs were low enough to not be too worried about it.

The US is different of course and I do always get insurance cover when travelling there (I would typically not bother when travelling to Europe). I don't get anything specifically for diabetes, and in fact the insurance cover usually doesn't cover this as a pre-existing condition, which is fine by me.