1. How to write something and have it can cancelled but still have it there just with a line between the letters.

2. How to write text that lead to a link? Eg "click here"
When u click that ^
It shud lead to a link. How to do that?

Not entirely sure what you mean by 1:

However to do the second thing, just take a thing of text like click here and do [ur l=link]click here[/url].

I think you mean it crossed like this?
Mark the part you want to have crossed out and click the 'S' next to the YouTube symbol right above your field of text.

And the the click here stuff, again mark your text that should link to stuff and click the globe (on the upper left side of your text field) insert your link and you're ready to go.

@Typhon not sniped this time, since I answered both questions

Thnk u and yes I meant like that ^