Paint for Windows 7 and 8 includes a basic text placement tool, but it only lets you edit text that you just placed. The moment you close a text box in Paint, the text flattens, becoming part of the picture. Unlike more advanced photo editors, Paint does not support layers, so to edit existing text, you'll have to delete it and retype it.
Place and Edit a Text Box
Select the Text tool and click to place a text box. As long as the text box is open, you're free to edit the text. In addition to typing or deleting text, use the settings on the menu bar to edit the text's formatting, such as font, size and color.
Edit Existing Text
Once you close the text box, you can't open it again for editing. The same holds true for text that's part of an image, such as a speech bubble in a comic. Your best option in Paint: delete unwanted text and replace it.
Click Select to pick the selection tool. To help select text in tight spaces, open the Select drop-down menu and choose Free-Form Selection.
Drag to draw an outline around the text you want to remove, and then press Del.
Choose the Text tool and click to place a new text box. Write your next text and drag the text box by its border to position it precisely. Click outside of the text box to finish.