Can I create a button that searches and presents all card with a particular label?

[Gary Kuipers]

For Instance

Label "Christina" would have a button which wuld find me all card with that label

[Gaurav Kataria]

If it is just one board then you can create a filter https://support.atlassian.com/trello/docs/filtering-for-cards-on-a-board/

If you need something to search for cards across all your boards, then you could create a dashcard https://www.atlassian.com/blog/trello/dashcards-powerup