What is the difference between 삼총 and 아저씨 ?Feel free to just provide example sentences.

First of all it is, '삼촌'.

So when you want to say 삼촌 as an uncle, Everyone can use it.

when you want to say 삼촌 as a middle aged man, Only little kids can use it.

when you want to say 아저씨 which means middle aged men, you have to be at least 20n years younger than the age of the person you are using against.

Like:
A= You
B=Middle aged man

A is 9 years old
B is 45 years old and he is your uncle.
In this case, you have to call him as 삼촌 since he is your uncle.

A is 43 years old
B is 45 years old.
In this case, you can't call him as anything since the age gap is less than 20 and you are not a kid.

A is 9 years old
B is 45 years old.
In this case, you can call him as 아저씨 or 삼촌.


A is 20 years old
B is 45 years old.
In this case, you can call him as 아저씨 but not as 삼촌 since you are not a kid.