Question Dropping/Slow WiFi unusually

[Skyreach]

So I recently moved back to a place I used to live at where I used to get fine download/upload speeds and latency with little to no cutting out. That was when I used my laptop, im now using my PC and getting only 1MB/S download and 0.2 MB/s upload. I cant use ethernet as the modem is on the other side of the building (which is quite far) and my laptop was in a very similar spot that my PC is in now.

I also tried doing a speedtest on my phone; next to the router I was getting 87MB/s download and 42.4 upload, while I was across the house next to my PC I was getting 5.30 MB/s download and 28.1 MB/s upload on my phone.

My specs are
Modem: Huawei B315
Motherboard: ASUS Z170 Pro Gaming
WiFi Adapter (USB): TP-Link ARCHER T4U Wireless-AC1200
OS: Windows 10

I feel like it might be the range or the adapter.

QUICK EDIT: When tethered to my phone my speed is a lot better but it is quite unstable.

 

[RARRAF]

maybe a powerline network adaptor might be a good idea