Add form controls programmatically and save data in different lists

Hello @Cumatale,

Welcome to Plumsail Community!

There is no way to programmatically add controls to the form out of the box, but probably you could add HTML control to the form and dynamically add controls with JavaScript to it.

And to get values from other lists and create new list items, you can use PnPjs library. Please see a good example in this post:

Also, you might be interested in Populate dropdown with data from the SharePoint list from another site collection article.