I convert my Jupyter Notebooks to PDF files with the 'nbconvert' and 'notebook-as-pdf' modules with the following on the command line:
jupyter nbconvert --to PDFviaHTML <mynotebook.ipynb>
The images(png files)referenced in Markdown cells that show in the notebook, won't be rendered in the generated PDF file. I reference the images in MD cells either with:

or
<img src="relativepath/filename.png">
As a workaround i can download the notebook as HTML within the Menu "Download as...". The images are properly rendered in the generated HTML file (given the images are provided at the right location, here 'relativepath' subfolder of the notebook's directory).
Does anyone know of a working solution? (I primarly tried to use the PDF via LaTex converting solution and unfortunately had issues with it on my M1 Mac Laptop, which is why I used the PDFviaHTML solution in the first place).