What do you need for WiFi in a small apartment?
I want WiFi in a spot where I don't have a wireless signal right now
Don't you have WiFi in the bedroom, or do you want wireless internet on the balcony? With a powerline adapter, you can create a WiFi network in a place where you don't have reception right now. This is simple, you just plug the adapter into the socket and connect it to your router. Plug the second adapter into the socket in your bedroom, for example. That way, you'll have internet throughout your entire apartment. You won't have to pull any cables, the internet runs via the AC power.
I want WiFi in my entire appartment
With a powerful WiFi router or a WiFi mesh system, you can ensure WiFi throughout your entire apartment. Do you want to place a router in the center of your apartment? You'll only need 1 router. Is your internet currently coming in from outside your apartment? Choose a mesh system with 2 stations. The WiFi points in such a set work together, so you'll have reception of the same network everywhere.