Correct or not correct

Hy.,

I am from Portugal, my gradson asked me to help him with his english homework - to translate and comment the text below.

After reading it I realise - in my opion - that the text as mistakes - I left school a long ago but from what i know i think the text should not inclued this words marked in red.

Am I right?

Thanks for helping

EMorais

At one time, I used to think that jogging was simply too impossible. I can remember a time when just a two-minute
dash to catch a bus would leave me with red in the face and barely be able to breathe. The turning point for me came when a very persuasive friend talked me into the accompanying her on a four-kilometre run round the local park. I managed just five minutes before which my legs decided they’d had enough. l think it was that image of my friend as rapidly disappearing into the distance that it stuck in my mind, and led me to take up seriously a sport which has genuinely and benefited y health, state of mind and fitness. My love of jogging is now about three years of old and is prone to the natural peaks and troughs that affect by most enthusiasms. Recently, I’ve been going jogging just once a week. But I’ve reached the point where, however many long I leave between runs, I can still go out for twenty minutes, and feel any better for it. I guess there is a risk of gradually losing out my fitness, but having overcome the problem before, I know it will never be so difficult again.