Hello Muhammad Awais,

You have to set the _order option into your specific models
For that you can arrange the fields on Ascending and Descending Order using ASC & Desc keywords

For Example :
class AccountInvoice(models.Model):
_inherit = "account.invoice"
_order = "partner_id asc, related_patient asc"

related_patient field must be storable field if you are using as related field

class Appoinment(models.Model):
_name = "appoinment.appoinment"
_order = "partner_id asc"

partner_id field must be storable field if you are using as related field

If the changes have been not reflect into list view then upgrade the your module properly in your database