Can anyone share me the steps for doing load test for urls with user name and password.
In SOAtest, I would use a REST Client to submit the HTTP POST for your login page. Your REST Client could be parameterized with usernames and passwords from a data source containing your test logins. In Load Test, you can create a project that references the SOAtest test suite containing the REST Client.
You can also consider using SOAtest's "Smart API Test Generator" to simplify creating REST Clients from your browser's HTTP traffic with the "Parasoft Recorder".