MANY Wifi Issues (from 5GHz to "no networks found") on my Dell XPS 13

I bought my XPS 13 about two weeks ago, and ever since, I've been having the following issues in regards to Wi-Fi to the point where I am about to throw this computer out the window. I have tried literally everything I could find online (from reinstalling the network driver to tirelessly restarting both the laptop and the computer). So please, help me out...

1. I cannot connect to my 2.4 GHz network. I put in the right password, but my laptop insists that it cannot connect. Without Wi-Fi, I cannot even run the troubleshooter program anyway. The funny thing is that every other device I have (other laptops, phones, and tablets) connect to the same network (with the same password), but XPS 13 does not...

2. Why can't my laptop detect 5 GHz band? It did detect and even connect to my 5 GHz band for one day, but then the next day, my laptop could not even find the same network (which other devices can still find and connect to).

3. After not connecting to any networks for 2-3 minutes, my computer all the sudden decides that it can no longer find any networks. You restart the computer and it does the same thing for 2-3 minutes. Why??

Obviously, I think it is the computer's problem and not my home wi-fi. However, I go to Starbucks, and my computer connects to that wifi immediately... So maybe my home wi-fi is not compatible with my computer? Who knows. Also, I am not a computer expert, so I may have messed up some tech terms, so bare with me. If there is any way I can explain myself better, let me know.