I need to purchase a more powerful hunting rifle, but I am worried about the recoil. Would the recoil of a magnum rifle be similar to a 12 gauge shotgun with magnum shells?
I recommend you to try AR-15 it is the most popular rifle. It is a semi-automatic version of the United States military M16 rifle that is marketed to civilian and law-enforcement customers. Also I can say that you need to choose good modern scope, for example there are great smart optics from ATN https://www.atncorp.com/smart-hd-optics it will be great choice.
Take a look at the “Expanded Shotgun Recoil Table” and compare it to the rifle cartridge you are considering in the “Expanded Rifle Recoil Table.” Both can be found on the Tables, Charts and Lists Page. But be advised that, subjectively, shotgun recoil bothers most shooters much less than equivalent rifle recoil because shotguns are usually fired from a dynamic standing position while the shooter concentrates on the target. Rifles are fired from a static position, and the shooter’s attention is on the sights. Try shooting your shotgun from a bench rest at a rifle target, slowly squeezing the trigger for best accuracy as you would a rifle, and see how it feels.