Hi there, Nkem Nwosu!
What seems to be the problem? Is it that you can't think of anything to write about? Topics are almost unlimited. Write about what you know, or don't know and would like to know more about (but do your research!). Why not make your first hub about the reason you decided to join HubPages!
Don't know how to get started? Once you know what you want to write about, just press the "start a new hub" button at the top and right. Then just follow the directions.
You can add pictures and videos to your "hubs" or essays --- really what "hubs" are, are long-form essays. But since your just getting started, I suggest you just write your hub and add pictures and/or video later.
If you start it and need to finish the "hub" another time just hit the "Save Unpublished" button and it will be saved for you to work on another time. You may keep it "saved unpublished" as long as you need to. When you are ready to display to the world, just hit the "Publish Now" button.
Why don't you start with that. Remember, if you want to dress up the hub with pictures and/or videos, you can always do that later.
Don't worry, its really easy. If I can do it (as computer illiterate as I am) anyone can!!
Take it easy.