What router are you using? And what WiFi mode are you using? 2.4ghz? 5.0ghz? 2.4ghz is more subject to interference (Bluetooth and microwaves interfer with it for instance) and has a slower throughput, but a longer range. While 5.0 is faster and less interference, but has a smaller range.
And download WinMtr and do a tracert for at least 100 packets to the closest server near you and post the results.
- US West server: 24.105.30.129
- US Central server: 24.105.62.129
- Americas (Brazil) server: 54.207.107.12
- Europe server: 185.60.114.159 / 185.60.112.157
- Korea server: 211.234.110.1
- Taiwan server: 203.66.81.98
And download an app called WiFi analyzer, you can download it for Windows or Android. Make sure to choose a WiFi channel that isn’t heavily congested.