Weak Wi-Fi usually improves more from better router placement, fewer obstacles, and adding coverage where it is truly needed than from random setting changes. Before buying an extender, check which rooms lose signal and whether the problem is wireless coverage or internet speed itself.
Test signal and speed in several locations
Compare performance beside the router, in the problem room, and at a midpoint. If the connection is already slow beside the router, adding wireless coverage will not solve an internet-service or modem problem.
Move the router to a more central, open location
Avoid hiding the router inside metal cabinets, behind televisions, or on the floor when a more open location is available. A central, elevated position reduces the number of walls the signal must cross.
Use the right band for range and capacity
Higher-frequency bands often provide more capacity but weaken faster through walls, while lower frequencies generally reach farther. Let a modern system steer bands automatically when it works well, or test each band to see actual performance.
Add an access point or mesh node when one router cannot cover the home
Long homes, multiple floors, or dense walls may require more than one radio location. A wired access point usually provides the most stable connection; a mesh system can be easier when running cable is not practical.