Hope you take a look at https://www.breakdown-notes.com https://www.breakdown-notes.com It has a pretty big map (though not infinite) for you to add shapes and

Hope you take a look at https://www.breakdown-notes.com https://www.breakdown-notes.com It has a pretty big map (though not infinite) for you to add shapes and text to, has support for adding and editing paths, plenty of tutorials and you can make slides in the paid version (free 2 week trial). Disclaimer: I made Breakdown Notes