Though I appreciate your eagerness to jump into deer hunting because it is a wonderful life experience BUT do it slowly. You are going to have to become a competent, safe shooter first and foremost. Since you have not indicated any previous experience I am going to assume that you have little. Before you grap a high powered rifle start small. Buy a pellet gun or even a 22 and go to the range and practice, practice, practice(this is of course after any required safety courses are completed). I always use the 22 to hone my shooting skills so don't think I'm suggesting this because of recoil. You have to work your way up to big game hunting. As to your question on deer rifles... 270 win, 308 win, 30-06 springfield are all good choices to start with as well as literally countless other calibres up for the task. The above three are excellent all around calibres that will work in a wide variety of situations. I'm glad you want to give hunting a try. It will be life altering.

i agree 100%. I noticed I was a little rusty with my 30-06 at the range. So I went home, grabbed my ruger 10/22 and put over 300 bullets through it (at a cost of $.016 cents each - you can afford it!). I fired from every position, standing, prone, kneeling, etc... Carved out a number of bullseyes.

Then I picked up my 30-06 and grouped 3 at less than 1.5 inches at 100 yards benched. It's not the best, but the deer won't know the difference!

You don't say where you live. I know some eastern states don't allow the use of high powered rifles (such as those suggested above), thus you might want to get a 12 gauge. Then you can hunt birds too.

I vote for 30-30. They're inexpensive, effective and reliable. It'll get you going, and from there you'll likely find something you like better from the choices others have listed.