All three of the statements you listed are correct.
Here is a breakdown of what each of these function keys does in Microsoft PowerPoint:
F5 (Start Slide Show): Pressing this key launches your presentation in full-screen Slide Show view, starting right from the very first slide.
F1 (Open Help): This is the universal help key across most Microsoft Office applications. In PowerPoint, it opens the Help pane where you can search for features, tutorials, and troubleshooting tips.
F7 (Check Spelling): This key automatically runs the spell checker tool, scanning your entire presentation for spelling errors and typos.