Can Bedroom area can be extended on the cantilever Slabs?
A cantelever is a projection from a support and this can be in many ways. One need to see the entire scheme and various things to comment.
To answer your question stand alone, yes it is possible to cantelever a bedroom. Now the question is how much. You should be meeting the strength requirement ie basically the moments and shear.Then comes the deflection. If the member sizes can be adequate to meet these requirements and if the supporting members can be schemed to suit, it is possible.
If there are restrictions on these then we need to look at various options.
There can be no stand alone answer for this question. It is all about the scheme.