Have you ever?

No, but I like rock music.

Have you ever been in a traffic jam?

Yes, several weeks ago. There was a snow storm in the middle of march (this is very unusual in the city were I study). It taken me about hour to get from university campus to train station by bus and tram (usually it's under 30 minutes). I was standing at bus for most of time, so my leg were pretty painful (because of traffic jam  ).
Have you ever finished Turtle philosopher with perfect score ?

No, I don't know it.

Have you ever swam in lake/sea/pond...?

Yeah, my family used to go to lakes all the time. And now I live near the ocean, so that's fun too. Wait, no, it's a pain because sand.

Have you ever felt bad after telling someone how you feel about something negatively? Like if they asked if you like their shoes and you say that they look ugly.

Yes, many times. However, I felt bad after saying I like something I don't like at all much more times.
Have you ever drawn or written something at your desk at school ?

Yes, but it was something unimportant, I think.

Have you ever seen a dead body?

A real one, no. Have you ever used the 'Send this topic' function?

I have once on another forum. Or at least pressed the button in an attempt to send it to my mail for later revisit, but something went wrong and I decided to just email it myself. Never used it again.

Have you ever been pulled over by the police and got off with just a warning?

No, I never had any problem with police.

Have you ever traveled by boat?

Yes. I've spent several of my holidays rafting.
Have you ever written a personal letter (to your friend, partner, relative) ?

Yes, to my parents many years ago when I was younger. It was some school trip I think.

Have you ever read a book with more than 500 pages?

Yes, many times. I like reading.
Have you ever flied in airship or hot air balloon ?

No. I haven't flew in a blimp nor a hot-air balloon, but I do wish to fly one somewhere in my life.

Have you ever wanted to play a prank on someone but that person knew your prank and did something to make it worse for you than for him?
Example, you want to throw a pie in his/her face, but instead he/she blocks and it lands partially on you, but not on him/her

No.

Have you ever witnessed an accident?

Fortunately no.
Have you ever won some race or competition ?