Congratulations with your purchase. It is a place to start and the way into mastering RC helis is probably very individual. The Walkera does get a lot of bad press on this site but I have no personal experience with it. Putting in a better radio should be a good idea - if you can get it to work with the electronics in the Walkera.

Before you start experimenting I should say: get a training landing gear. And consult some of the excellent web sources on how to learn to fly a RC heli like:

Radd's School of Rotary Flight and Electric Helicopters Beginners Guide (should be easy to google).

Be prepared to face the fact that you will crash, you will need to do repairs - it's part of the hobby.

Good luck,
Bing117