Add cards to a video:-
To add cards to a video, follow the steps below. Up to a total of 5 cards can be added to one video.
1. Sign in to YouTube Studio.
2. From the left menu, select Videos.
3. Click the video you’d like to edit.
4. Click the Cards box.
5. Select Add card. Next to the type of card you want to add, select Create.
6. Customize your card and click Create card.
7. Adjust the start time for the card below the video.
8. Changes are automatically saved.
Types of cards:-
Here are the different types of cards that you can use to customize your content. You can also use YouTube Analytics to get performance reporting for cards.
1.Channel cards:-
Link to a channel that you'd like to call out to your viewers. For example, you could use a card to thank a channel that contributed to your video. You could also use a channel card to recommend another channel to viewers.
2. Video or playlist cards:-
Link to another public YouTube video or playlist that viewers might be interested in. You can choose to link to a specific time in a video.