Research means diving into the unknown.
Committing to work on a research project with a mentor is also diving into the unknown.
What I can reassure you about is that
Professors are used to undergraduates signing up for research projects with less preparation than would be seen in grad students
The stakes will not be as high for this as they would be as a grad student. If you don't have any original findings to show for yourself at the end of the project, that won't be a disaster.
This is a chance for you to get your feet wet, to ask, I wonder... and then figure out how you might start working on an answer.
Give it a try!