Well, you are likely to get almostas many answers to the "perfect" rifle and cartridge as there are members on this site.
Some will swear that NOTHING beats a 30-06, others will swear by a .270 or maybe a 7mm-08, etc. Yes, use that to guide you but you don't have to settle for just those choices.
Before settling on one, my own advice is to get with some of those friends and such and go out and shoot a few different types and calibers. Take that along with what and where you will be hunting and talk it over here or with someone at a gun shop you can trust. Then make your decision.
The real thing you have to worry about is picking what is right for you.
Then practice, practice, practice. Shoot it often enough to know your weapon inside and out. And don't just shoot it at a bench. Shoot prone, kneeling, sitting on the ground, standing, braced and unbraced, so you can pull off the shot in the feild.
The saying, "beware a man who only owns 1 (gun), he probably knows how to use it" can have as much meaning for hunting as anything else.
I have quite a few of my own to chose from.
30-06, 25-06, 30-30, 35 Rem, 7mm-08, 7mm TCU, .270 Weatherby, .300 WSM, .375 H&H, 45-70, .243 ........ (you get the idea.

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And have them in lever, bolt, single shot and even a pump.
But what I pick up time and again is my Ruger #1 in 7x57. There are others that may be better in some cases, maybe technically better in most all cases, but I know that gun inside and out. It might not be the best choice for you, or anyone else here, but that is MY rifle and I am at my best with it more often than with any other.
So good luck, and Good Hunting.