I found this link when it comes to English prepositions, https://blog.udemy.com/in-vs-on/

When it comes to watching TV, we say it's "on" TV,  I suppose because it seems like the image was on the surface of the Television screen.  But we can also say my favorite actors  are "on TV" when they are "in my favorite shows or "in the video" or "in the film" that was played "on netflix or on youtube..  But if I go to a movie theater, I might say they are "on the big screen" and other time I would say they were "in the pictures"   I never noticed the strange convention of English.  I think the history of using "on" comes from when we would project the film onto a screen. I am not sure why we say "on the phone" or "online" but we do. 

I don't mind your use of slang "wanna" as it is common where I live. But it's not proper grammar for business or school. I tend to use "wanna" when talking but not when typing. 

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Hi Kevin,

Writing a notebook is a great way to start with iTalki  :-)   .    People are very helpful -- usually the notebooks that you write will get corrections from native English speakers.

It is fun to participate in the discussions in the community discussions area, too.

Here are some corrections for your first notebook:

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