Unable tlo get session ID

Hi,
i am trying to invoke endpoint(salesforce) by using HttpRequest but getting an error.
My question is to invoke saleforce endpoint and get session Id.

Any one knows or any samples.

Have you tried the same in postman? @sunilraju

Actually, when REST API is available, then you just need to the URL, which will navigate to the particular web application, package, method, and class within that , Infact for some, you need to know the query params as well.

I think these all you know ofcourse, but when you pass the URL and the inputs required, may be the body or the headers, to the required type of request i.e., GET or POST or whatever, you will get a response. Have you tried anything till now? Can you post the response you got?