Add this repository to HACS, then:
HACS > Integrations > Pronote

Copy the pronote folder from latest release to the custom_components folder in your config folder.

Click on the following button:

Or go to :
Settings > Devices & Sevices > Integrations > Add Integration, and search for "Pronote"

Then follow the step of the config flow:

Note: if you're using a Parent account, you'll be prompt to choose a child:

This integration provides several sensors (where LASTNAME and FIRSTNAME are replaced):

• sensor.pronote_LASTNAME_FIRSTNAME: basic informations about your child
• sensor.pronote_LASTNAME_FIRSTNAME_timetable_today: today's timetable
• sensor.pronote_LASTNAME_FIRSTNAME_timetable_tomorrow: tomorrow's timetable
• sensor.pronote_LASTNAME_FIRSTNAME_timetable_next_day: next school day timetable
• sensor.pronote_LASTNAME_FIRSTNAME_grades: a list of the latest grades
• sensor.pronote_LASTNAME_FIRSTNAME_homeworks: a list of your child's homeworks
• sensor.pronote_LASTNAME_FIRSTNAME_absences: a list of your child's absences
• sensor.pronote_LASTNAME_FIRSTNAME_evaluations a list of your child's evaluations

The sensors above are updated every 15 minutes.