UK prescription, moving to Canada

This is a little specific but absolutely any advice is really apreciated!

I'm from the UK and am about to move to Canada on a working holiday visa for two years. I want to live in Western Canada, specifically Vancouver/Edmonton and spend a winter on a Ski hill possibly Banff or Whistler. These are incredibly loose plans (obviously, what with the ADHD lol) but would involve me being pretty spontaneous and moving around relatively often.

Ive been diagnosed for about a year and take 50mg Elvanse & 5mg Amfexa every day. I've only just learnt that I can only bring 30 days worth of my meds with me, and not 90 as I initiallly thought. There's no world where I can go without, so I'm panicking a bit at the idea of only having a month to sort my meds.

Please correct me on any of this but my understanding is that my UK prescription is not valid in Canada. Initially I thought that was just a formaility and that I could just show a doctor in Canada my prescription and they would write me a Canadian one, but it seems like in Canada doctors are incredibly reluctant to prescribe them even to those diagnosed in Canada. I'm worried that my diagnosis and past prescriptions actually wont count for anything. Canada has walk in clinics but I've heard they arent able to prescribe controlled drugs, so I dont know if there's any point me trying those once I'm there. I've no idea if I'm able to get a family doctor what with my visa and I imagine that'd take a lot longer than a month.

Even if I am able to get a Canadian prescription I'd be moving every so often and would have to use different pharmacies, which I fear would be flagged in some way what with them being controlled drugs, making it even harder to get them.

I really dont want to have to call off my trip for this so if anyone has done anything similar or can speak to getting prescriptions in Canada plz let me know : )