Hi @AbdulAfrad-6528 ,
There is currently no way to accomplish your needs through JSON, but you can try using Power Apps to customize the SharePoint list form, which is more flexible. I found some articles for your reference:
https://learn.microsoft.com/en-us/power-apps/maker/canvas-apps/customize-list-form
https://www.matthewdevaney.com/power-apps-customize-a-sharepoint-list-form/
Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link.
But Power Apps is not currently supported in the Q&A forum, if you need to get more details about using Power Apps, you can go to the Power Apps community to post a new discussion, and you will get support for Power Apps. Hope this gives you some ideas.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.