Maybe not 100 MBPS throughout the house but at least solid signal strength throughout the house? Is that possible?F you want 100 Mbps throughout the home on wifi, you'll need a router that can deliver about 3000 Mbps in the room where the router is located. Prices probably start at 30K or so for such routers.
Netgear R7000 is going for ₹11K right now on Amazon. Excellent router and It also supports third party firmware. You could also consider the Asus RT AC68U if don't mind spending extra bucks.