No internet access on the laptop?

I can connect to the Wi-Fi, but it doesn't work. It always says, "No Internet access". It's not because of our Wi-Fi but to the laptop, because I can connect anywhere with my cell phone, etc. Without any problems.

does anyone have any idea why that is?

Maybe restart the router or unplug the power cord and wait 10 seconds and plug it in again, otherwise just waiting until tomorrow helps in most cases.