How to increase how far your iPhone 6 will find WiFis?

I have this problem with my phone where it won't connect to my house Wi-Fi from my room. I know it's not the internet because it worked wit my old iPhone 6. What can I do

Change the antenna

Make sure you are connected the the 2.4Ghz band of your Wi-Fi if you have a dual band router. That band is designed for longer distance. You may want to call/chat or go into an Apple store. They can run a diagnostic on your phone and see whether the antenna is good or bad.