You need to get your ISP to help troubleshoot the issue with your router. If the Steam Deck works fine on other networks that’s a very strong sign that it’s not the Deck that’s the issue.
Most public libraries have WiFi or computers that you can use in a pinch, leverage those as much as possible. You are paying for those services via taxes, they are yours.
but how will i type ‘IDKFA IDDQD IDSPIDSPOP and IDNOCLIP’ on the Deck with no keyboard?!