Me with measurement ! if a square can become a rectangle can a rectangle become a square?

Actually, every square is a rectangle, since the angles in a square are always right angles. That's more than saying that a square can be a rectangle; it is one.

And since squares are rectangles, you know that some rectangles are squares--namely, the squares are!

We teach children "this is a rectangle, that is a square. The rectangle's sides are different lengths". But when you grow up, it's important to think of the square as a SPECIAL rectangle, because it is all that a rectangle is, and more.

A square is still a rectangle, but it's not just a rectangle, it's a (pedigreed) square.
In summary, yes a rectangle can be a square.

Hope this helped :)