I have booked two tickets online. The tickets are to fly from China to Dubai and from Dubai to Afghanistan. Where can I fetch both of these tickets from?
Paper airline tickets are pretty much a thing of the past, replaced by electronic, paperless systems. When you made your flight arrangements, you will have been given confirmation details, usually a combination of numbers and letters, along with your identifying information (name, or surname).
Using that, you go to the airline(s) web site to check in for the flight(s), generally 24-hours before departure, enter your information, and the database will retrieve your flight record, confirm that you've checked in, and lets you print a boarding pass. You can also check in at the airport, either at a kiosk using the confirmation number, or at the counter by showing your government issued ID card or passport.
As you booked through an agency, contact it now if you don't have what you need to check in correctly, and easily, when the time comes to travel.
This sounds confusing but when you book online you are issued a ticket and given a ticket number to identify it, although you may never actually see a paper ticket.
Often with that ticket number, which is usually a series of numbers, technically called e-ticket number since it refers to an electronic ticket, you can access information regarding the reservation through the website of the airline. It is often possible to print from there an e-ticket receipt which can serve to show that you are indeed traveling, even though it is not really needed since they airline will lookup your info at check-in time using your passport (or other valid national ID for domestic flights).
After booking, online or in-person, you are also almost always given a Booking Reference which is a code of numbers and letters. That is the most common way to look up reservations and it may refer to a number of tickets if you booked several at once (either for several flights, for several people or both).
If you have a smartphone, then you can use your airline's app. This will show the ticket details. There will be a QR or other bar code. This will let you get through security, and boarding.
If you don't have a smartphone, then you should have received an email that contains a PDF. You print this out, and use it for security and boarding.
You can also log into your airline's website, and download the PDF ticket from there.
In all cases, there will be one ticket for your outbound flight, and a second for the return.