RE: Interested in boar hunting, many questions.
As pigs only see about 50m tops and 30m with any clarity that’s not your biggest problem but they can smell anything so watch the wind. A 12ga and a load of SSG Buckshot is my preferred medicine for pigs in the thick country and a Rifle is good all round but if money is an issue try some buckshot for your first few hunts as I haven’t shot many pigs past 50m I don’t consider range to be a problem.
If you want a rifle for pigs then a 30/30 isn't to bad but the Marlin is better then the Winchester from my point of view, and a good bolt action in 243win up to 30/06 is plenty of power for any hog.