How to edit text from image in photoshop?

The key thing to remember is that you can't edit the text directly. It's 'baked into' the image as pixels. So, your job is to remove the old text first. Your best bet for this is the Content-Aware Fill tool. Just loosely select the text you want to remove using the Lasso Tool. Then, go to Edit > Content-Aware Fill, and Photoshop will magically replace it with the background.

For more complex backgrounds, the classic Clone Stamp Tool gives you more control. Once the old text is gone, simply grab the Type Tool (T) and add your new words. A big tip is to match the font. Photoshop even has a 'Match Font' tool to help you out. It makes the final result look seamless.