Just getting into Networking

[Marsrover91]

So, to start I never really cared to much about internet speed/latency or whatever. Just bought what the ISP told me and connected the router they sent. Recently I set up a NAS server and a Ubunto computer that I use for Jellyfin and some stuff. I noticed that uploading files to my NAS server from one computer (ethernet directly to switch) was getting slightly lower speed than my other computer (ethernet directly to switch). So I started doing some digging and did some speed tests online. Both speed tests did fine but they were swapped when it came to speed and latency. Computer one download speed (average between ookla and cloudflare) was around 650 MBPS with 10ms latency download and 400MBPS with 90ms latency upload and the other computer (average between ookla and cloudflare) showed 300MBPS with 2ms download and 260MBPS with 5ms upload. I am just confused why it would be swapped when both setups are on the same switch same everything.  Any thoughts or ideas on how to fix. Both are Dell laptops and they live about 2 cm apart from each other.

[OddOod]

Your file transfer doesn't go to the internet
What do the source computers have for CPU? That can bottleneck you