Mapping Resources to Azure Functions

Hi,

What is the best way to achieve the following using APIM and a function app?:

I want the api to contain two resources:

GET /resource1
GET /resource2

The data is coming from a Azure Function app with two functions called GetResource1 and GetResource2

Do I import the API from the Azure Function, or an OpenAPI spec and do the mapping myself? How do I do this mapping?

Can I auto generate an OpenAPI spec in my Function App project somehow? Should I do it by hand?

Ultimately looking at doing this from an ARM template - but not got to that bit yet!!

Any help or links would be welcome.

Thanks

Graham