Be very careful you are seeing the numbers correctly. Many speedtest sites are in mega "bits"/sec. A lot of file/game download use mega "bytes"/sec.
In general if speedtest gives you high number there really is nothing wrong with your internet connection.
I assume you have steam or epic or a similar site. Try to download a large free game from one of those sites. Do you get the same download rates. There could be differences in the path your data takes to the different data center locations. It also could be some issue microsoft is having. all this is out of your control
Unless there is some issue with the software client doing the downloading there is very little you can do to affect the transfer speed. All the basic network function on your PC are functional since you get good numbers on speedtest. Speedtest is actually a file download and upload except the file is not kept.