You can easily import images to your notes from any other Windows 10 app, such as Photos.
Do the following:
In the Windows 10 app of your choice, open the folder containing the photo or image you want to send to OneNote. For example, open the Photos app and then browse to any folder containing one or more images.
On the menu bar, click Share.
In the Share task pane that opens, click or tap OneNote.
From the drop-down near the top of the OneNote window, select the page where you want to send the selected image, add an optional note, and then click or tap Send.
When you open OneNote for Windows 10 later, the added image will appear at the end of the page you selected. You can then move the image exactly where you want it.