Those steps will only work when internal/external applications will invoke webMethods or the inbound to webMethods authentication and not when webMethods needs the token from internal/external application?
/invoke/pub.oauth/getToken is the token endpoint for Integration Server. That is, when Integration Server is acting as an OAuth authorization server, that is the endpoint you call to get an access token. If you are using another vendor’s authorization server, call the token endpoint on that server.
If you are using the authorization code grant or the implicit grant, you need to initiate the grant process by calling the authorization endpoint first: /invoke/pub.oauth/authorize. If you are using the client credentials grant or the resource owner password grant, you can call the token endpoint directly. Please see the IS OAuth documentation and the OAuth standard for a more complete explanation. If you are using an external authorization server, see the section on that topic in the IS documentation.
for the Token we need to get it from 3rd party API.
we were able to get the token as response after calling it from SOAP UI but when we call the service through flow service then pub.client:http we are getting the html page format as response.