how do I apply a different deck box sleeves and coin?

Honeygun

I recently got the prismatic evolutions deck box leaves and coin and I want to use it for my deck, but I do not know how to apply it to my deck or make a different one using it. Please give me your feedback on it and give me an answer to my question or send me to a link, please and thank

Honeygun

and I tried to use them, but it doesn’t make any sense to me and I make a new deck, but it was just using the default ones

Eremas

https://community.pokemon.com/en-us/categories/pokemon-trading-card-game

here's a link for you to follow.