2 answers
You have few optionsOut of the box, there are no relationships between Opportunity - Quote X Order, if you want to auto populate order line item from Opportunity line items or Quote then you have to write 1. Apex trigger2. Process Builder with Flow 3. AppExchange app that will help you to "​Automatically Generate Orders from Opportunities or Quotes" ​https://appexchange.salesforce.com/listingDetail?listingId=a0N3000000B5iwHEAR Thank you. This is the area where improvements are urgently needed in future releases. Sales cloud seriously lacks rich functionality beyond opportunity managements, this is 7 years too late since 2009. This is weakness has been constantly exploited by rivals NetSuite and Oracle alike which have rich cloud-bases features all the way extending to back office.