Please refer to the below guide. Once you click on "Send in email" > It will open the image as an attachment in the default email program which you have configured in your system.
https://www.shorttutorials.com/windows8-paint/s...
On the "To" field add your email address where you want your email needs to be sent.
Please refer to the following guide if you want to change your default mail app.
https://kb.wisc.edu/helpdesk/page.php?id=170
Let me know if you still need help. :)
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There are links to non-Microsoft websites. The pages appear to be providing accurate, safe information. Watch out for ads on the sites that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the sites before you decide to download and install it.