Code :

def _get_basic_product_information_purchase(self, product_or_template, pricelist, combination, **kwargs):
# Initialize basic information dictionary
basic_information = dict(
**product_or_template.read(['description_purchase', 'display_name'])[0]
)

# Add the product_or_template ID to the basic_information dictionary
basic_information['id'] = product_or_template.id

# If the product_or_template is not a product variant
if not product_or_template.is_product_variant:
basic_information['id'] = False # Reset ID to False
combination_name = combination._get_combination_name()
if combination_name:
basic_information.update(
display_name=f"{basic_information['display_name']} ({combination_name})"
)

# Get the standard price of the product_or_template
price = product_or_template.standard_price

# Get the purchase order ID from kwargs
purchase_order_id = int(kwargs.get('id', 0))

if purchase_order_id:
# Browse the purchase order using the ID
purchase_order = request.env['purchase.order'].browse(purchase_order_id)

if purchase_order:
# Find the seller linked to the purchase order partner
seller = product_or_template.seller_ids.filtered(lambda s: s.name.id == purchase_order.partner_id.id)
if seller:
# Use the seller's price if available
price = seller[0].price

# Return the basic information along with the price
return dict(
**basic_information,
price=price
)

thank you very much for your helps but it seems that it not reach what i desire. actually the id of what i am going to get is from purchase.order and if i try your below code i dont even get any id
but if try straight search of id in purchase order it worked well
price = product_or_template.standard_price
purchase_order = request.env['purchase.order'].search([('id', '=', self.id)])

for rec in purchase_order:
seller = product_or_template.seller_ids.filtered(lambda x: x.partner_id.id == rec.partner_id.id)
if seller:
price = seller[0].price

any idea? im stuck in this