It's ok, I know you must be busy, but I ha've been waiting forto hear from you.

"waiting to hear from" someone means you are waiting for some communication. You would say "waiting for you" if you were waiting for them physically, like at a restaurant or something.

EverythI'm doing is fine for me now.

Your original sentence doesn't sound natural

Your description reminds me of the late autumn morning, when the fields and the rivers will bare covered with a thin layer of mist, like yarn.

"Yarn" doesn't really fit here, at least for me it doesn't remind me of mist.

I went to a farm as an intern at the age ofhad a job on a farm when I was seventeen.

"Intern" or "internship" is usually more used for professional environments, like if you worked at an office for a summer. For this kind of thing (if I understand correctly), job is probably better.

I remember it was in early October in the Gregorian calendar.

"in the Gregorian calendar" is unnecessary

In the mornings, there are a lot of fallen ginkgo leaves on the roads, and you can smell itstheir bitter breathodor.

"their" instead of "its" because there are multiple ginkgo leaves, not just one.

It's been raining here these daysrecently, and the temperature has dropped toby more than twenty degrees.

I shot a video aboutof the fallen leaves on the road and I will send it to you.

I will also send you a few photos I once shot at the Shangri-La Pudacuo National Park a decade ago, because I think they have the similar scenery to the pictures you sent me.