1) My question is, to please let me know the difference between a Prophet and a Messenger?

2) What will be the difference between a normal Rasool and an Ulul’azm Rasool then?

1) Every Messenger is a prophet, but not every prophet is a messenger. A prophet is one chosen by Allah, receives revelation or divine inspiration, and is infallible. A messenger is a prophet who also has an official message to his people (like a new religion or scripture). Many prophets did not have an official message. They were just sources of guidance to the people.

2) The Ulul-azm Rasouls are very distinguished prophets who have the highest level of faith and willpower. They are the greatest of messengers and the most high ranking.