In terms of performance, the best option is multiple wired together access points. You can get flat Ethernet cable that can easily fit under doors, carpets and through windows if you don’t want to/can’t drill any holes in your walls. Mesh networks are an option, because the mesh nodes generally have higher power transmitters then your device, but this will be slower then a proper setup, and get slower the further you are from a node with a wired connection.

If you are on 5 GHz, try moving to 2.4 GHz, the top speed is slower, but it much better at passing through walls.