you need to check if the barrel and see if it is loose even just by a hair if it is then you need to twist it to the point where it is accurate then take out the hold pin for it and reset it
If the sights are fixed, they can't be adjusted. You would either need to replace them with adjustable sights, or else use the "Kentucky windage" method of compensation.
adjust rear sight up for distance
Depends on the firearm.
No. It describes the sight picture on the target.
By drifting the front sight
Via the screw.
Fire one round, note strike, adjust sight to that point, fire again, repeat.
Adv - longer sight radius Disadv - bulky
The owner's manual has instructions.
adjust the sight it might be broken
You sight it to a specific range , e.g. 100 meters. Clamp the rifle to a solid object, or use a benchrest. Shoot at a target and adjust the sight accordingly, until the holes in the target zero in to the sight.
Best left to a gunsmith