File complaint against builder before consumer forum as he has provided less parking slots than required as per DCPR 

They can file a complaint before the consumer forum of appropriate jurisdiction seeking spaces and compensation.

Yes, if the builder has not provided car parking space as per the approved plan and the master plan the builder can be dragged to consumer forum for compensation and other remedies also.

Directions can also be avail against builder from court to provide parking spaces as per DCR or compensation if parking allotment is not possible.

You can file complaint before consumer court  that builder not alloted parking as per DCPR.

1. Society should send a legal notice to builder for providing parking space as per DCPR 1991.

2. If builder doesn't give satisfactory reply then Society can file case against builder in civil court and claim compensation for breach of contract.

Dear Sir,

A RERA complaint can be filed against the builder for not delivering the promises amenities to you. You can file a case against the builder with RERA Authority of the State in which your property is situated. The RERA Authority will evaluate your complaint and proceed with the matter by calling the builder to appear before it. You can ask for compensation, ask the builder to provide the amenities within a particular time or cancel your booking with refund. To file and represent your RERA complaint, you must consult a RERA advocate in India who can draft and file your complaint in an error-free manner and represent your side before the RERA authority or adjudicating office.

Yes you can approach consumer court in the same