Go to chrome://network#state (on your school chromebook of course; if this is blocked then ur kinda screwed lol).

Scroll to the bottom of the page; you should see a list of "favorite" wifis that you've connected to in the past.

Click the + sign next to the wifi name of each network that you commonly connect your chromebook to.

The more wifis you expand, the better, but note that they have to come from the "favorites" section.

Use ctrl+a and ctrl+c to copy all the text on the entire network#state page.

Go to caub.glitch.me.

Paste the copied text into the textbox below.

Press the "generate onc" button below the textbox.

Once you have downloaded the file, go to chrome://network#general

Click on the "import onc" button

Import the downloaded file