Edit the text in textarea with Input?

All welcome!
Help, please.
How to realize the possibility that entering information in the input text in the textarea has changed on a specific line, and opredelennoi length.
1) And that works for me always on the last line, and I have to go to a certain place and at a certain length
2) And how to remove zadvoenie text. I need to (for the Text of the query + Text input) was, if I erase the text from inputa it works only the text of the query
https://codepen.io/anon/pen/MxMmEY
thank you
March 19th 20 at 08:55
0 answer

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