Yes sure.. So basically.. all living cells contain DNA which contains the instructions of how a particular cell works.. you can think of it as a code as well.. just like u can edit a computer code or change it.. similarly with the help of specialized tools, the DNA can be edited. Just like you can write a computer code to do a particular task.. we can do the same thing with DNA using CRISPR....
For example lets say a person is suffering from the deficiency of a particular hormone which is responsible for growth..it is possible to take the dna of this person..insert the particular code that contains instructions for producing that hormone.. nd thus treat this deficiency..
Basically we can remove inefficient or harmful codes from the DNA and replace them with better ones.
There are many other implications nd i suggest you watch the videos to get the scale of this thing and what people have actually already done.