Question

punctuate the fallowing letter with punctuation
o yes said the father I can at least do that much

Answer 1

"O Yes!", said the father, "I can at least do that much."

Since O yes seems to be exclaimed, we used the exclamation mark.

We use inverted commas for direct speech

Before using inverted commas, commas are used.

At last of the sentence, full stop is used

The first letter of the sentence is capital.

The first letter in the inverted commas are capital.