I've been on my laptop since last night, no Wi-Fi reception, so I did a network diagnostics. Problems were found, but since I have no idea of anything, I would need someone to tell me what to do now.
"Problems Found: The adapter (Realtek RTL8723B Wireless Lan 802.11n USB 2.0 Network Adapter) has driver or hardware related issues."
https://www.drwindows.de/hardware-and-treiber/130454-treiber-realtek.html
Since you copy the error times and look, whether something comes, that helps you.
I would first turn off the modem router briefly and then turn it back on, so it restarts.