welcome to the forum!
i do not see an error?
if you would run this there would be an error because the input line is commented out.
your problem is entirely unrelated to jupyter though.
I also have the same issue. whenever I try to input a value, the code cell turns into a markdown and after that, the notebook is hanged.
I think this was covered here although it is hard to be sure because you didn’t provide version numbers and just a couple of screenshots.
I’m having the exact same problem. Jupyter Notebook 7.2.1
Tried 7.2.0 and had the same problem. 7.1.2 still the same problem.
Bizarrely I can enter the digit 7 but as soon as I type any other character it goes wrong!
Type a 6 and…
Yes, where I reference posts by Okosa_david discuss updating not fixing it. Okosa_david had hoped to reply what trying on a fresh machine revealed.
My suggestion would be a clean install and not just updating, if that was the case.
Or try JupyterLab as discussed there.