Application control section, there you find these functions. If you connect the tab reference to the property node, you can select available options. Right click gives you the option changing between read and write mode. I cannot check your vi now, recently i am on holiday.
Because you have to hide one of the page and unhide the other page. This for loop executes twice therefore. You can do it without the for loop, but then you double the number of elements. Actually in real application I put all these into a subVI.
Hm, i cannot edit my prev post, I am from mobile phone 🙂 So if you do not see how this for loop works, I would really recommend you to start the official LabView training from Core 1. Check what online content you can access with your licence (Labview self-paced learning).