This is a you thing. You have to provide ALL the pertinent measurements, in a drawing. ALL OF THEM. Start with drawing it out, to scale, and then draw out your existing furniture to scale.

"I want to redo my bed room side of my apartment..."

Confused. 18' x 26' = 468 square feet. Are you trying to fit three bedrooms, a master bathroom and a "small toilet" into this space? Or is the 468 square feet for a master bedroom, a two-child second bedroom, and a bathroom? Or...

Yes in a 26x18 I wanto fit in a master and two children rooms, and a small toilet and a big toilet in the

You need to move to a bigger place. One that you own.