Obtaining a Birth Certificate for Someone Born in a Different Country?

I’m really hoping someone can help!

I’m wanting to apply for Canadian citizenship as my biological father is Canadian. I was sure he’d been born in Canada but moved to the uk as a young man (so my mum had told me, but she passed away 3 years ago)

Anyway, I applied for, and received my birth certificate last week. He was actually born in Germany :wall:

Now, I’m pretty sure my grandfather was in the Canadian military so I’m thinking he was posted to Germany when my father was born. I’ve spoken to a immigration lawyer and he’s confirmed that if my grandfather was posted in Germany when my father was born then I can still get my citizenship.

I know NOTHING about my father, I’m 36 and I haven’t seen him since I was 3, so I know even less about my grandfather. I need to get my fathers birth certificate to find out my grandfathers details, to then apply for his military records (if there is one!).

So my question is: how/where do I get my fathers birth certificate????