For the first red, you don't need an article before "relationship".
When you're saying "type of [word]", do not put any article before that word.
Example: "a type of device"
Not too sure about the "your back" parts. It could be your teacher does not like repition.
Also not too sure about "did". He probably wanted you to use the word "felt" instead of "did feel"
The first word of the last paragraph should be "in" not "at".
The red commas definitely do not need to be there.
Don't know why he marked "time to" and "to" red.
That footnote can play a large role in helping Karim better understand the myth, because instead of just listing the source, it gives a bit of history about the subject.
Answer: what the question here?
Explanation: u only mentioned some names
<h2 /><h2 />
I believe that the context is if you help you always get something in return