Two sets of data: the first is the hardware and software inventory, and the second is a Wi-Fi overview.
Please download and run (free) EtreCheck, and share the results to the clipboard. Then open a new reply here, and press the Additional Text button that looks like a printed page, and paste and post the hardware and software configuration report here. From that, we can get a little more detail about what is installed and what is running here.
On Mac, the basic Wi-Fi environment characteristics are visible when using Option-Click on the Wi-Fi logo 🛜 in the menu bar to capture some Wi-Fi network data.
For us to look at the Wi-Fi network data here, post the items shown in the Wi-Fi display including the Security mode and from Channel to NSS inclusive (Security, Channel, Country, RSSI, Noise, Tx Rate, PHY mode, MCS, NSS) (without posting the Wi-Fi address, any local HotSpots that might be present, the network name, or the BSSID), and we can take a look at the basic network environment. You can the screenshot as necessary.
if there are any “coffee shop” VPNs installed, remove all, restart, and test again.