I think it would be best to check with a travel agent in Qatar for your visa from Qatar. or better yet, check with the Chinese Embassy in Qatar.
I think you would have to hold a QID to apply for a Visa from Qatar and a letter from your local sponsor. - Which is a standard practice for people who need a visa before travel.

If you have a visa, you can travel from anywhere before the validity of the visa expires. The visa will have a use before or end date.
All the best.