Daedalus is an official full node wallet, which means you download a full copy of the Cardano blockchain and independently validates every transaction in its history.
Once you have downloaded and installed the app, please create/restore a wallet and let it sync completely. When done, you can now delegate your stake to KOPI as below:
Yoroi is an official light wallet that does not download the blockchain when you open it. It can be accessed as a Chrome extension, or as a phone app (iOS and Andriod).
Once you have installed the Chrome extension or app, you need to create/restore a wallet. When done, you can now delegate your stake to KOPI as below:
The Cardano Delegation Cycle is as shown on the left.
Some IMPORTANT points to note: