it is difficult to build a gaming PC for under 400 bucks even without a hard drive and
from what i know the parts in your country are even more expensive than in USA , UK , or europe ...
one solution would be to start without a dedicated graphics card and temporarily settle for IGPU
another would be to buy used PC , you should get more performance for less money this way ,
but of course it´s always a risk .
with your budget you can´t afford anything more than 2+2 pentium G 4600 ,
some cheap b250 chipset motherboard , generic pc case , cheap power supply and 1x8gb ddr4 memory module ,
and the rest to spend on graphics card
(but you would not have money left for anything more than the radeon rx 560 or nvidia gtx 1050 (non Ti version ) )