1
The date problem is the most likely cause of the Internet problem, if you are unable to change the time in BIOS, at the bottom right of your Desktop, is that clock also showing the same incorrect time?
2
Boot your system into BIOS, find the option to restore BIOS Defaults (usually F9 key in BIOS), then check if the date and time are correct or if you can set the correct time.
If not, click your Start Button, then just type msinfo and press Enter, please provide a screenshot of the resulting System Information window.