Noob Question: Ability to pickup items and use them

Have you searched YouTube for any tutorials or looked in the tutorials section here:

https://docs.unrealengine.com/latest/INT/Videos/

This one covers a speed pick up:

https://docs.unrealengine.com/latest/INT/Videos/PLZlv_N0_O1gZg3dTMetmsfm_s4lb4-Tg0/8bqM7kl4al0/index.html

Hi! I’m sorta stumped over a small feature I want to figure out - the game I’m working on will require the player to pickup speed boosts along the track that they can store and then use later with the press of a button. These would be the only power ups in the game so I guess the inventory system would be extremely simple, however I’ve got no idea how to go about this. Thanks in advance