I can write it, sure, but that's the "give a fish/teach to fish" analogy. Assuming you're wanting a person to reach a certain cell in Excel, you would write a program that waits for the user to navigate to or click on that cell, and then you'd fire the code that launches a dialog box asking them for the picture.
You're not telling me if you're just in a spreadsheet, a form in Excel (easier, actually, in this case), a specific worksheet, or something else. Also, you've not mentioned what this picture is for. It almost sounds like you're trying to write a database application in Excel. While that's technically possible, it's a giant pain in the ass for anything beyond simple lookups.