For that you can override the name_get method in the 'res,partner' model to return the name plus the sur name if you have a field that contains the Mr. or Mrs. values. for example

class ResPartnerInherit(models.Model):     
    _inherit = 'res.partner'
    
    sur_name = fields.Selection([('mr','Mr.'),('mrs','Mrs.')])   

    def name_get(self):
        result = []    	
            for rec in self:
                result.append((rec.id, '%s - %s' % (rec.sur_name,rec.name)))
        return result

Happy to help :) an upvote will be awesome