On selection how to load fields associated with it or new doctype

On selection how to load fields associated with it or new doctype in erpnext.

On selection of with nomination <Rs.10000 user should get new form which will get submit and complete by his supervisor or else on other selection form will be submit to Co user.

To trigger field visibility, you can customize the form and set Depends On on the fields you want to display

https://docs.erpnext.com/docs/v13/user/manual/en/customize-erpnext/custom-field#11-additional-details

You can also accomplish this with a Workflow and specify conditions for the greater than or less than.

https://docs.erpnext.com/docs/v13/user/manual/en/setting-up/workflows