Out of 36 equally likely outcomes, 6 satisfy "Sum equals exactly 7".
The event is about 1 in 6.0, meaning you expect it roughly once every 6.0 rolls.
With two d6 dice the most likely single sum is 7, with a 1-in-6 (16.67%) chance. Values near 7 are more common because more combinations produce them.
Possible sums range from 2 (all ones) to 12 (all sixes).
Next stepTry the "Sum distribution" chart below to see how the probability is spread across every possible total, or increase the number of dice to see how it shifts.