What Billy said. There are ways and means of using the standard sights with both red dots and magnified optics, it all depends on your preference and the overall use of the rifle.

Tell us which sight you looking at and we can give a better answer.

For a non magnified red dot there are ways of keeping the irons useable while having the dot as well. Either what is called an "absolute co witness" where the red dot and the irons are all in the same plane, but the irons obscure some of your red dot sight, or a more popular "lower 1/3 co witness" which means your irons appear in the lower 1/3rd of the field of view of the optic. You can still use them if you need to, but they are not blocking your view.

There are certain parts needed to get either system to work, but they can be done.

Things get complicated by magnified optics, but there are also ways around that.

KBK