Hi 

You can use required=True in the py file where the field is defined, otherwise in the XML View 

<field name="field_name" required="1"</field>

if it is an inherited view use the position attributes 

<attribute name="required">1</attribute>

Regards

try this way:
example:

1. Make sure that in your model, the field amount_total has the attribute required=True:

from odoo import models, fields

class MyModel(models.Model):

_name = 'my.model'

amount_total = fields.Monetary(string='Total Amount', required=True)

# Other fields and methods

1. In your view's XML definition, ensure that the required attribute is correctly set for the field:

field name="amount_total" required="1"/>

i make it in python and in xml but still didn't work