Agreed. Acrylics is the choice of paint for simplicity.
Michaels carries a wide variety of all brands in many colors. I favor Ameiciana brand. It's a bit more costly but well worth the texture it delivers and ease of application.

Since you are just beginning, I would suggest that you purchase some less expensive canvas along with your final choice. This will allow you to experiment with texture and technique at a lower cost to you (as you may not want to keep them, depending on what your trial creations are...You never know though, they may turn out beautifully...An artist is always their own worst critics).

zycloP is correct about keeping a rag handy for quick corrections. Due to the simplicity of Acrylics, though, you do not need paint thinner. (Paint thinner is primarilay for oils). Acrylics are water based only, so you'll need a jar of water nearby.

A wide variety of brushes provides you equal variety of results. Again, spend some time with some creative exploring.

You will need a palette for laying out and mixing your paints.
I've never actually purchased one myself (been painting for years). I've always tried to think of economical means .... using plastic lids from used food tubs, like from a coolwhip tub, margarine tub, anything like that. They have actually proven better as they have a lip surrounding it, which holds anything which may try to run off, and serves as a great edge for scraping any excess paint off of the brush. Not to mention that once the paint dries, it merely peels off of it...great for clean up. Tub lids allow you to have many on hand with no extra expense.

As I said, you'll need a jar of water handy to keep brushes from building up too much paint. Swirl brushes in water, tap of excess, and (depending on the effects your creating) you can either use that excess amount of water left on brush to apply to your work in progress, or wipe the excess water from brush onto that handy rag.
Personally, I have many rags handy..a clean one I keep beneath the jar of water (which I use for quick "clean" wipe-offs after a rinse in the water), and 2-3 others I use to completely wipe brush clean.
So long as the brush doesn't build up too much paint at the base (where bristles are held on with the metal clip).

What I've discovered to be the ultimate wonder of easement for working with Acrylics is what is called "Floating Medium". It is essential for the allowance of extending the paints drying time AS you work with it. I LOVE THE STUFF. I'm lost without it. The best offered (in my opinion) is offered by FolkArt. Ask any of the clerks in Michaels to assist you in finding your materials.
And yes, for final preservation, once completed and finally dried, you can also use the matte spray on your paintings, as well as on charcoal, as zykloP had mentioned. That stuff is great!

There are also "how-to" books out there, but I've personally never found them useful enough for their price (most are quite pricey).
In my opinion, trial & error is the best teacher....Not to mention, fun, fun, fun. I Love Painting.....on anything!

Everyone has their own technique. And depending on the medium used, each tecnique is equally unique.
I paint on many different mediums, with canvas falling as one of the last on my list. (I paint many murals. I use tecnique in a large array, which requires much longer time for completion. I'm always seeking anything which aids in making the paint easier to work with longer..lol).

I hope some of this has helped. Any questions, feel free to pm me.

Happy painting.

Shangrala