Hi Ganshyam,

You can call 'ir.model.fields' create mandatory values: {'name':'fieldname','field_description':'feild label','ttype':'boolean','model_id':model_id, 'state':'base'}

Other properties like readonly, required etc. you add in this dictionary.

Make sure you should pass state = 'base', by default it is manual that could be consider as custom field and can easily delete from odoo admin, but for base you can't delete from odoo admin, for custom fields you need to add prefix 'x_' to every field name.

If you're trying though python script you can refer https://www.odoo.com/documentation/10.0/reference/orm.html