In Lichess there is a limit of 64 chapters for a study.

Do we have the same here? If so, is it possible to change that?

I ask the question because I have the idea of creating studies for Tjalling courses, the limit would hamper the project.

Almost all the limits that lichess has apply here as well, which includes the 64 chapters limit. If that ever becomes a practical problem we can always talk about increasing it, but maybe it would be better to split the material over multiple studies anyway, as I'd imagine working with more than 64 chapters in one study can be quite cumbersome.