Please suggest using %pip install wget. It is the current best practice for installing from inside a running Jupyter .ipynb file.
The magic install commands were added in 2019 to insure the installations occur in the environment where the kernel backing the active notebook is running. Use of an exclamation point alone doesn’t do this, see here about the modern magic commands %pip install and %conda install. More about the shortcomings of using install commands with an exclamation point is at top here.
The magic command variation also works in JupyterLite and finally Google Colab and so to my knowledge they are pretty much universal now, whereas the exclamation point is not useful in JupyterLite.