rotate image in notes app

If you're using your MacBook Air, as your post suggests, YES you can!

After inserting the image, hover your mouse over the image.

There should be a small "down arrow" at the top-right of the image.

Click it.

Select "Markup"

After the image opens in "Preview", find the "Rotate Image" icon in the toolbar.

Click "Done".

Your image, in Notes will be rotated!

This action cannot be done inside of Notes on any other device, however. You'd need to save it in your Photos app first, rotate it there, then add it to a Note.