Results from the latest French Bac exams for all academies are available at https://resultat.studyrama.com/bac/ .
Select the academy from the map and select the letter that corresponds to the first letter of the student's last name. Alternatively, use the search bar to type in the name. Results for previous years (going back to 2016) may also be available via the Internet Archive database, but may not be comprehensive.
An additional source for online results, https://ocean.siec.education.fr/publinet/resultats, also includes results for other national examinations such as the BTS, BEP, CAP or the Concours.