MAke sure you have a Github and Unity account setup.

Go to: education.github.com/pack

Click on Get Your pack

Sign in to github

If asked select authorise this application.

Click get benefits

Click on the Unity redeem option.

Finally click on the Activate button.

You will need to have your Github accoutn verified first, this can take a while.

You should then have access to the Unity Student plan.

Check your email for a Unity student plan licence key.

Open Unity hub

Sign into your account.

Click on manage license

Choose Unity Plus or Pro

Enter your serial key

You now have a Pro version of Unity on your student plan.