Rails Form multiple parent child updates from single form

I have a form for creating Orders... It updates the Orders and order_items tables simultaneously.... I have to create for orders for each material we buy each month. It is tedious to go back and forth... I would like to create one form which lists all the materials we buy and a few details about them... and allows me to select the order details from the same form id name av_purch av_use Request Supplier Qty Pack_size 1 AAA 200 199 220 Sup_A 4 50 Sup_B 1 20 2 BBB 30 30 30 Sup_C 1 30 I would then like this to create multiple orders