How to Dynamically Fill other Form Field depending on Field Selection?

Hello
Can someone help me on this Topic?

How can i Fill Form Field in my case “meal” and “price” depending on the Menu Selection from the Select Field.
Menu is Custom Post and the Select Field provides the post_id of different menue
I want if i change or select a Menu that the meal change also according to the menu (post_id).
I tried live value and lot of different stuff but i still didnt come to a sollution.
Thank you in advance
Best Greetz