What a silly, silly question.
a) A man's sexual skill is only tangentially connected to the size of his penis, if at all. Having a big, small or average penis has nothing to do with whether one can "satisfy" another person.
b) A woman's satisfaction in having sex with a man is only tangentially connected to the size of his penis, if at all. Most women care a lot more about the man the penis is attached to than they do the penis itself.
c) Even if b were not true, strangely not every woman on the planet is the same, and what would satisfy one would not satisfy another. Some women like big penises, some like small, some like no penis at all.
I say these things with confidence despite never having sex with a woman, never intending to have sex with a woman, and never having had a conversation with a woman about what she likes in bed. "We hold these truths to be self-evident," as they say.
As for the pure numbers, 6.5" is average-to-slightly-above-average and perfectly normal.
So basically, upshot is - stop worrying and enjoy yourself.
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Edited to Add: I apologise if this comes off as unnecessarily tough and a harsh welcome considering this is only your second post. But really, it is one of those questions which is just pointless to ask because there's no possible answer and the asking of it in the first place reveals misconceptions galore.
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