I'm not going to tell you what to buy. I know what I'd get but rather than try to sell you on a particular light I will list a few points that will make it a bit more possible to do many things with one light.
Go with 2AA, not too long but more importantly not so short it gets swallowed up by your hand. AA is an easy to find and cheap battery with the option to use the best rechargables for noobs, the Eneloop.
Think before you buy about how you plan to carry it, loose in pocket - clipped to pocket - holster........ Look for the feature or accessory that will help you do this. Look at a lights loaded weight, it helps to know beforehand.
Get a click switch on the rear and learn to use it, one handed operation is very handy!
Get at least 2 modes, a low and high is good.
Get something that has decent throw since you
can't make up for the lack of throw if you really need it.
Get something that can use a diffuser so you can use it up close without being blinded by a hotspot.
Something with a warm or neutral tint may help you ease into LED's especially if this is going to be an outdoor use light but it is not a 100% need.
Don't get hung up on getting a huge amount of lumens on high, this is an EDC right - NOT a special use battery hog.
Those are fun but this is not what you really need at this point.
:welcome: