Flash is easy to use but can be difficult to learn. It doesn't take long to learn, but it can be confusing at first. Once you understand how to use it, it's actually really easy to work with. And yes, you could do it all using only Flash. It has sufficient drawing tools to allow you to animate entirely in Flash; Almost every Flash animator only uses Flash for their animations.

There are probably tutorials you can find, but I never had to use any. You can learn basically everything just hitting F1 and using the help files.