How to make REST API Calls

I am trying to make an API call, for example action=login with the following URL sample
Since the documentation doesnt specify if this call is a POST or GET am only assuming its a POST.

My body is as follows
“partnerId”: 261462,
“userId” : “”,
“password”: “wgnd8bWGND*B”

With that i get an error response “>MISSING_MANDATORY_PARAMETER : partner_id”

What could possibly be the problem? Or what is the structure of the API calls?

Also…on successful login, does the response contain a bearer Token
One of my goal is to be able to make stateless API calls.

Please help

I have tried this on trial version as well as self hosted community version

Hello @kennan,

Please see loginByLoginId using JSON content type returns USER_WRONG_PASSWORD
as well as