^^^this^^^

if you think about how your rifle and scope are setup, the line of sight (thru scope) and the line of barrel are at a slight angle, barrel is slight upward of the line of sight. as the bullet leaves the barrel, it will cross the line of sight twice in an arcing fashion, once on the way up (line of barrel), then once on the way down as gravity starts drawing the bullet back to earth. Typically, using 1 inch high at 100 yards for "most" centerfire rifles, gives you a 0-200+/- invisible tube that the bullet travels within a ~3 inch diameter of the line of sight. this starts at ~1.5 inch below line of sight (distance between center of scope and center of barrel) leaving the barrel traveling at a slight upward angle (mentioned above) crossing the line of sight and hitting 1 inch high at 100 yards. Gravity is in play as soon as the bullet leaves the barrel but due to the slight angle it appears the bullet is rising (it's really not, just the slight angle in effect). After the bullet passes 100 yards the arc of the bullet path will slowly start falling back towards earth and around 200 yards, it is back to being 1.5 inch below the line of sight.

Think of it as having a 3 inch diameter tube that you are shooting thru with the bullet leaving the barrel at the bottom of the tube ... it will arc up to the top of the tube around 100-125 yards and then fall back to the bottom of the tube about 200 yards. So, in theory under perfect conditions, if you put the cross hair on the middle of the shoulder from 0 to 200 yards you are within 1.5 inches low or high of where the crosshair is placed.

edit: this will vary slightly depending on caliber, bullet and powder, elevation, pressure, temperature, etc. ... some are flatter shooting, some have more arc ... the above is just general information

Setting your scope for 1" high at 100 yards means that when your crosshairs are on the bullseye, the bullet hits the target 1" above the bullseye. Don't overthink this. From 50-200 yards you should be able to aim directly where you want to hit the deer and you will be within a couple inches from that point of aim. That will put your bullet in the kill zone. Good luck and let us know how it goes.

^^^^^that's all you need to know

Thank you so much Pitchfork Predator,

My scope is adjust 4 clicks to represent 1 inch of scope movement (sorry I am sure I am not talking right language, still learning)

So for my case I will adjust scope by 4 clicks up., so POI is 1" higher

Thanks phathawg,

I still do not understand why I am adjusting up 1" in higher?

PMK lined this answer out for you above...

Well, Goodo, I thought phatdawg said it as basic as it can be but tech savvy guys cant believe how basic they have to go for me sometimes so ill try to expand.
You must not understand that if you adjust your scope so that you aim at the bullseye and actually hit the bullseye at 100 yards then at longer distances that particular adjustment will cause your bullet to drop so low that you wont hit within the kill area of the animal. If you INSTEAD make that scope adjustment so that you hit 1" higher at 100 than you actually aimed then it wont drop so far at the longer distance to cause you to miss the kill area. Also, keep in mind that once you have made the proper adjustment you theoretically wont have to readjust again(ever) unless you have a malfunction with the scope. If you still don't get it then keep asking and others can try. All kidding aside, our school teachers DO NOT get paid enough.

At 100 yards adjusting it to be 1 inch high makes it 2.2 inches low at 200 yards. If you had it dead on at 100 yards, you would be more than 4 inches low at 200 yards. More than 4 inches is getting close to needing to hold higher on the target which you don't want to have to do. By being 1 inch high at 100 yards, you're giving yourself the easiest way to not have to adjust for any distance. See the chart which I set for your caliber and factory load.

You understand perfectly. Yes some scopes will differ for what each click represents. You are good to go.

OK, imagine you're shooting at a 5" target. At 100 yards you're hitting dead center. At 125 yards, aiming at the same point, the point of impact is lower. The farther you are from the target, the lower the bullet hits until at 200 yards the bullet is near the bottom of the target and may completely miss the target. There's no holes in the target above the center. By adjusting up 1", the 200 yard shot is now on the target without worrying about bullet drop and the 100 yard shot is hitting 1" high but still well within the kill zone. This way all you have to do is aim where you want to hit the deer and you will be close enough to insure a kill. The 5" target is the kill zone on a deer. If you can keep all your bullets in that zone from 50-200 yards, you are good to go. Hope this helps. Don't be scared to ask questions. Like they say, the only stupid question is the one you didn't ask.