M2 Mac mini won't connect to Wi-Fi

Edit: ah, and now there’s an image with the Wi-Fi data.

You’re on 802.11n in 2.4 GHz, which won’t be speedy. Noise is high, too. Your signal-to-noise is bad.

Update and restart the Wi-Fi router, and please post the Etrecheck data.

Given you’ve “tried all troubleshooting available online”, and given what has been tried was omitted, contact Apple and start a service request.

If you want us to look at the details and the Wi-Fi network data, post the items shown in the following image including the Security mode and from Channel to NSS inclusive (Security, Channel, Country, RSSI, Noise, Tx Rate, PHY mode, MCS, NSS, green highlight) (without posting the Wi-Fi address, any local HotSpots that might be present, the network name, or the BSSID, all of which are expurgated from the image shown below, red highlight), and we can take a look at the basic network environment.

Please also download and run (free) EtreCheck, and when the run completes share the report to the clipboard. Then open a new reply here, and press the additional-text button that looks like a printed page to get a text input box big enough to paste the hardware and software configuration report here, and paste and post that report here. Add-on VPN apps and other add-ons can cause routing or throughput issues, for instance.

Also whether the Wi-Fi router is running current firmware, and whether that device has recently been restarted.

Adding poorly shielded USB cables, drives and devices to the Mac mini can cause Wi-FI and Bluetooth interference..?

see > Resolve Wi-Fi and Bluetooth issues caused by wireless interference - Apple Support

If you have recently added any of those external devices, remove them and re-test the Wi-Fi signal.

If that helps, try moving the cables and devices so that they are not near or in-between the Mac mini and Router.