Please explain the difference
Ex.
I’m gonna be doing some traveling in Europe
I’m gonna travel in Europe
What I’m gonna be doing next
What I’m gonna do next
I’m gonna be telling jokes
I’m gonna tell a joke
Regards
Learner_2010
Where the action has a very short duration, the “going to do” version is preferred. For example you’d say “I’m going to hit you” (“I’m going to be hitting you” would be unusual). Conversely, when you want to emphasise the continuing nature of the activity, you might prefer the “going to be doing” version. For example, “I’m going to be travelling for the whole of July”. However, in a lot of middle-ground cases there seems to me to be very little difference in meaning between the two versions.
I urge you not to get into a habit of writing “gonna” routinely. Outside very casual (or knowingly casual) writing, or direct quotes of casual speech, it looks very sloppy.
Dozy is very polite, but I urge you not to write ‘gonna’ at all.
well explained Beee
thanks you Bee and Dosy
Sorry! I’ll quit my habit of writing “gonna”
but I’ve a question here.
Is it ok to use “gonna” in conversational English. or I just not use it at all, as I have seen a lot of movies and I hear “gonna” in almost all movies I have seen yet.
Learner_2010 
Very often, even though native English speakers think ‘going to’ in their minds, they speak quickly without though, and the words come out sounding like ‘gonna’, particularly in an informal setting.
That is the origin of such words.