Vacuum leak or brake booster?

Help, when pressing brake pedal nararamdaman ko parang mamatay ang makina. Sa hose kaya ito ng brake booster or sa brake booster itself? Mataas din pala idle ng sasakyan, pag bukas 900rpm then pag mainit na 1.5k rpm. Delayed acceleration and lose of power but definitely not sliding. Carb type engine.

Follow up question po, wala na pala nakakabit na hose sa advance ng distributor kailangan ba meron? How can i test the advance mechanism if it is still working? Kakakuha ko pa lang ng sasakyan. Nissan sampaloc engine.

Thanks.