A SIM card is required to get notifications and perform administrative tasks.
On the one hand, a phone number (SIM-card) is required to open a bank account, while on the other hand, a bank account is required to obtain a SIM-card. Doesn't it appear to be a loop?
Taking a prepaid SIM card is an option for foreign students and postdocs who do not have a bank account in France. Prepaid(Prépayé) plans are available through the following operators' websites:
Search for "Forfaits menses" and "sans engagement" plans, which mean "monthly" and that you are not forced to keep the number for a long period of time (say two years).
I bought an 80 GB/month package from free.fr for 18.88€ via an electronic machine at fnac in Châtelet Station in Le Centre Pompidou (Date: 26/03/2022). Other telecommunication companies have (at least) a desk in this mall and streets around it. You'll notice that if you search more, you might be able to get a better deal. There's always a cheaper alternative to a cheap!
In any case, I feel a suitable solution is close to 20€.
Please complete this text with your own experience