Completing the basic training on the Mother Base | Walkthrough MGS V: TPP Guide

Fulton out the stunned ally (the balloon with a cargo icon)

Get close to Ocelot who will give you a Fulton Recovery Device which is designed for sending away people, animals and the military equipment to the Mother Ship with a balloon. The game will allow you to test its functions. Stun a volunteer either by shooting him with a soporific ammunition, knocking him down or getting close from behind and choking him. Stand next to him and use the fulton button.

You may unlock the cardboard box when your research squad will level up

Choose your iDroid and select the Mother Base section and then the Staff Management section. Listen to Ocelot's comment and return to main menu. Choose the Development section and go to Weapons / Items. You will learn that you don't have enough resources so you may turn off the iDroid. Stun and fulton away few other volunteers.

When you will rise up the research squad's level you may return to Weapons / Items menu and select the C. BOX DRST. Confirm the order and wait for the research to finish. Choose on your map an area to drop the supplies and wait for the cargo to drop on the platform. Now you can finish the mission or start the optional activities.