how can i formally start and essay about a certain interest? Any suggestions?

Answer 1

I am uncertain of your "certain interest"

There is nothing wrong with opening with some drama...such as

Beekeeping has been my life for forty years.
or
War is hell.
or
Stamps can open a new world.

Answer 2

That depends upon the purpose of your essay.

Also -- the introduction is the LAST thing you should write. You need to know exactly what you've said in the body of the paper before you decide how you'll introduce it.

You also need to incorporate your thesis statement in the introduction to your essay.