Sounds like you're more interested in being given answers than you are in receiving help and guidance towards finding your own answers.
I will give you one answer and ask you to find the other two.
First, rearrange the given data 3 2 6 4 5 3 4 2 7 5 3 in ascending order. Since you have 11 data points, merely choose the point in the exact middle (that is, the 6th point). That's your "median" for this data set.
Your turn: look up "mean" and share the definition you find. Do the same for "mode."
Supposing you sum up the 11 data points and divide that sum by 11. What would this give you? What's its name?