Your query provides a tiny pinhole view on your issue that makes it difficult to advise. Some info that would help:
- What operating system version are you on?
- What software versions are you running: python, jupyter, fastai, fastbook?
- Which instructions did you use to install the software?
- Have you watched the LIve Coding videos?
- What other things have you tried that do work?
- Your snapshot shows cells with multiple lines, so how do you determine which line is the problem?