Standard advice to newbies.
1. Buy Sandee Cohen's Visual Quick Start Guide: http://amzn.to/k2bkxg
That's the best $20 you'll spend.
2. If you learn better by watching Lynda.com has some terrific video training. This link will get you a one week trial: http://bit.ly/fcGpiI
The first thing you want to look into are paragraph styles.
You should pick up sandee cohen visual quickstart guide from Amazon. It will get you much further than the forums.
to your questions.
1. On new document choose master text frame. Adjust margins to adjust frame size.
2. Adjust in your character panel or control bar. learn on paragraph styles to make life easier. Use font settings like I have here for a sharp B2B look. It will stimulate turnkey eyeballs and facilitate web readiness.
Yes you can do all those things and a trillion things more in InDesign and the other applications. But you need to undertake some training. There are lots of books and online training available, for example: Lynda.com. Set up some simple practise pages to get the hang of things before you launch into your masterpiece!
Think twice, though, about Master Text Frames.
In most cases they are not required to do what you might want to do (ID makes text frames on the fly) and they wind up being a real hindrence in many cases.