It really depends on your personal style, but my corrections to this are in bold. My personal comments are in green. 

 

 

Have fun

( If you want to use a salutation first, you should seperate it from the rest of the message.  But for it to have better flow I would put it at the bottom of your message. and rewtite it, I will put my verion in bold below)

 

 

I want to havinge a conversion*ation with others in English to find some for fun.

 

Let's  learn together!

 

*The word you used was "conversion", it has a few meanings in English. One is to change somebody to another religion. 

Example of a sentence using "conversion":  I am converting  from Catholicism to become a Jehovah's Witness.

Or another example: I am converting my money at the airport, so that I can pay with the correct currency. 

Another meaning for "conversion" is to  find out what something is by different standards, like the exchange rate between  American Dollars and Canadian dollars. Or covnerting something from Miles to Kilometers. 

The word you wanted was spelled in a  similar way, "conversation"  is a discussion, or talking.  But "conversion"  is  changing something from one thing to another. 

have fun

having a conversion with others in English to find some fun

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I want to have conversations with others in English in order to have some fun.

or

It would be fun to have conversations in English.

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