Is there a way to change text or data on a powerpoint grid while in the presentation mode. I want to be projecting and changing text on my laptop at the same time. Is this possible
Not in presentation mode, no. Presentation mode is intended solely for showing a PowerPoint deck, not for making edits to it.
If you want to edit your presentation, you'll need to be in one of the other views, such as slide view. If you want to make this as much like presentation mode as possible while still being able to edit your presentation, you can minimize the notes view at the bottom, minimize the notes view on the side, and hide the Ribbon by single-clicking on the Ribbon tab that is currently active. You can also go into fullscreen mode. This isn't a perfect solution, but it's the best workaround for having the most of your slide visible (like in presentation mode) while still being able to make edits.
If you just want to take notes during your presentation without making changes to a slide, there is a note-taking area in presentation mode.