First you must determine if they have the same denominator if they doesent have then.you must get their lcd or least common denominator
1/2 + 1/6
2= 2 4 6 8 10
6= 6 12
Their LCD is 6
Then 6 divided by the denomintor 2 is 3 times its numerator 1 then it is 3
The 3 is the numerator and 6 as the LCD
3/6
1/6
6 divided by 6 is 1 times the numerator 1 is 1
1/6
Then the ir denominator ids now the same you can now add
3/6+1/6=4/6