Question

How do you start a thesis sentence with the subject on computers? Is this sentence a thesis?

Computers are becoming more useful.

Answer 1

Good start, but not quite a thesis statement.
A thesis statement tells what your paper is about.

Include your reasons that computers are becoming more useful...(usually three reasons which will become your body of your essay)

Example:
Due to advances in technology computers are becoming more useful because they are very reliable, easily store data....