There’s a lot of ways to run JupyterLab and your post itself doesn’t tell us how you are using it.
I’m guessing what you show in your screenshot is JupyterLite because I see piplite mentioned.
It would have been better to include the upper right corner where there is an indicator of the specific kernel being used. Also that indicator of busy or not is important to using Jupyter.
I think what you are asking is already answered here at While using jupyterLite my notebook does not respond - #4 by fomightez .
Also:
If you are indeed using JupyterLite, you can now install things like numpy simple by the following:
%pip install numpy
There’s no need for two lines and a complex syntax to do this.