Cherry wants to know if a mesh router would work in a house made of concrete blocks? Leo says that concrete blocks need rebar to stay standing, and rebar turns your home into a Faraday cage, which blocks wireless signals, and that means no WiFi outside of the main room. It's death to WiFi, so Mesh may not help at all. But that isn't the only solution. Leo says that if you have CoAx in your home, you can convert that to wired internet. You'll need a NOCA adapter (Networking Over CoAx cable). You can also string ethernet, but the simplest solution may be powerline networking. You can actually use your electrical grid too for the internet. It's not as fast, but fast enough. TPLink sells them.
Another option is to put your mesh router in the attic. That will enable the signal to leap over the concrete walls as it comes down into the house. But it gets hot up there, so Powerline networking may be the best solution.