Number from another bookmark

Hi, i have two bookmars “Objednavky privatni” and “Kaumy”. In “Kaumy” a need to add new column with numbers from “Objednavky privatni”. For example. “Objednavky privatni” is ORDERS in english, and Kaumy is company name. If they made a order, i will make a new record in ORDERS. There is 6 product, they can order in different quatity. I need to get these quantity number into new column “Kaumy”. In excel is very easy. In airtable is work for hours! Thanks for help.