I'm adding some additional resources for LSF I found
This one has the LSF alphabet and some videos including one comparing Japanese, American, and French sign languages https://www.tradonline.fr/en/blog/french-sign-language-a-language-in-its-own-right/
This one is a LSF-ASL dictionary. I couldn't get it to work on my phone but it's really cool https://projects.lib.rochester.edu/lsf-asl-app/dictionary/n/a-g you search the English or French word then it shows videos LSF and ASL side by side
Here is a (non-exhaustive) list of free resources for different sign languages:
American Sign Language (ASL)
Australian Sign Language (Auslan)
Black American Sign Language (BASL)
British Sign Language (BSL)
Chinese Sign Language (CSL)
Emirati Sign Language (ESL)
French Sign Language (LSF)
Indian Sign Language (ISL)
International Sign Language (IS)
Irish Sign Language (ISL)
Japanese Sign Language (JSL)
Mexican Sign Language (LSM)
Plains Indian Sign Language (PISL)
Ukrainian Sign Language (USL)
Please feel free to add on if you know of others, be it more resource for one of the sign languages above, or resources for learning any of the other 300 plus sign languages.