Asking about Internet

Please help me answer!

In general, the school will not have any way to know what websites you visit if you don't use their WiFi. If you use 4g or another wifi connection the school will not see any of your activities online. (I am assuming the school is not doing anything nefarious like installing malware on your phone which seems unlikely).

You can also browse privately using the school network if you load an onion router such as Tor. Be careful though, these things can be tricky and if you make a mistake it could be embarrassing.

Thanks so much for your answer.
I confuse that If I use my cellphone to access Internet, after that I use Wifi of school. So, whether or not school know addresses that were accessed by my private service?

best not to do anything illegal or embarrassing while using your school's wifi - or on school grounds (some schools locally jam wifi coming from outside so students can only use school wifi - which is monitored)

Yes, if you use your schools wifi... they will know every website that you visit. There are ways around this, but it is easiest and safest to either wait until you get home, or use another way to connect to the internet.

Just in case anyone wants to try... there are a few basic options to use your schools wifi without them knowing what sites you are visiting.

1) You can use a VPN. If the VPN is set up correctly, it will mask your activity on the internet even when you use the schools WIFI. You need to be careful you set it up correctly... there have been some frauds where people have sold alleged VPN applications that basically did nothing.

2) You can use Tor. Tor is free... you can use it if you can follow instructions. Again, if it is set up correctly it will mask your activity online even if you use your schools Wifi. Again, you need to make sure you set it up correctly (make sure you understand and follow the instructions).

Thanks you very much for your helps!