To know if something can fit you go by the space inside.
Are those measurements outside dimensions?
If so, your case is tiny, I assume they're inside dimensions.
If so, your case can fit an ATX motherboard.
One way to tell is how many expansion slots your case has in the back.
That's a fast way to tell, I forgot about it before.
Count your expansion slots.
If you have 6 or more, it can take ATX.
5 or less it might not be able to.
Expansion slots are pointed out in that image.
Take a look and count yours.