Hello,
Instead of MSPaint, there is a better tool if you would like to remove an unwanted effect from the photo as the online version of MSPaint seems to me a little basic and doesn't expect AI Level.
We are talking about AI Object Remover:

This tool is amazing so let's take the following example:

With the brush, I could remove the image part:

Select part then click on Remove:

The final result looks like this:

Take in mind in free mode one download per day is available but the tool needs an upgrade for more than that.

This is the final output:
