What does 69 mean my বন্ধু were talking bout it and laughed when I asked what it is?????

People laugh because it is a very common term for a sexual position, and sometimes even as adults, we snicker at the sexual things... it's not you.

Wikipedia-however imperfect is still a good source:
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Basically in this position the two people's bodies resemble the shape of the number 69 with one person lying on their back and the other facing the opposite way/inverted atop so as to simultaneously perform "oral" sex- one on top, one on bottom so as in each other's face. It doesn't matter who is on the শীর্ষ অথবা if it is আরো "knelt over"~ (or even on their sides)-STILL resembles the shape of "69."

Hope that helps explain the basics there.
Now আপনি too can giggle whenever someone says "69!!!" ^-^

what does 69 mean

69 is a position were a person lays on his/her back while the other person stands/knee down and bends down as both face eachother's genitals and perform oral sex. they can also lay side ways and do it.

i think answer must me a cock sucking while having a sex