Depends on the firearm.
adjust rear sight up for distance
Best left to a gunsmith
You raise the rear sight. Actually the pellet gun is shooting straight, your sight is aimed too high. By raising the rear sight you are bringing the point of contact lower into view.
You can get a owner's manual for free at the S&W website
IF IN FACTORY CONFIGURATION, The front sight is fixed and not adjustable. The rear sight is drift adjustable for windage changes - you need to loosen the set screw that holds the rear sight in place. From what I've found, it may take some doing to get that set screw loosened.
Your eye is the rear sight.
Windage is adjusted using the knob on the right rear of the carrying handle/rear sight mount. There are two elevation adjustments. For the purpose of zeroing the weapon in, you would raise or lower the front sight post as needed. The front sight base is marked with an arrow and the word "UP" - this refers to which direction you would need to adjust it to bring the strike of the round up - it actually lowers the height of the front sight post.
Tap it gently. that's all it takes! This is from the manual: Your rifle has been sighted-in and test-fired at the factory. Due to individual shooting characteristics, however, sighting should be range verified. 1.) Vertical Correction (Elevation) To raise the point of impact, raise the rear sight, by moving the sight elevator rearward. To lower the point of impact, lower the rear sight, by moving the sight elevator forward. The sight can be raised and lowered by moving the stepped elevator forward and back with your thumb. To move the point of impact to the left, tap the rear sight base to the left. To move the point of impact to the right, tap the rear sight base to the right. Windage adjustments to the rear sight can be made by gently tapping the dovetail portion of the rear sight in the desired direction.
This information is for a pellet gun not a rifle with a scope. the gun must have an adjustable rear sight to work. Aim at a target 32 feet away and fire. (10 meters) If you strike the target to the left of the center then you need to adjust your rear sight to the right. If you hit the target to high. You need to lower the rear sight. If its to low then you need to raise the rear sight. I also suggest using match quality pellets, Do not do this on a windy day, it will effect the pellets accuracy.
I'm assuming you mean the iron sights mounted to the barrel of the rifle? Elevation is adjusted by sliding the sight elevator front to back on the rear sight. Windage is adjusted by drifting the front sight left-to-right. If the gun is 'shooting to the left' tap the front sight slightly to the left. A very small movement will have a major change. You could also tap the rear sight slightly to the right to effect the same change. If the gun is 'shooting low', slide the sight elevator toward the rear to lift the rear sight leaf. Again, a very small change in adjustment will have a big impact downrange. sales@countrygunsmith.net
Not sure I understand your question, but in general, any rifle with a front post sight, and a rear peep sight is used in a similar manner. The top of the front post is placed on the center of the target- and should be centered in the circle you will see when sighting through the rear sight. The rear sight is adjusted left/right and up/down to move the strike of the bullets onto the target at a given range. For military use, that is usually 250 meters. From there, the shooter may adjust the elevation for different ranges, or merely hold higher or lower on the target.
You can adjust the rear brakes with the rear brake adjustment bolt. The rear brakes should adjust automatically every time you back up and use the brake.