Hello
Hope you are asking about the Production order 
Try this
For Routing
1. Go to OPJG for your plant -> Select your order type and Create a Default operation without work center.
2. Go to OPL8 and select the order type -> in Routing Selection Put "0 - No routing or reference operation sets to be used".
By this settings the system will automatically select the default operation while creating the production order with CO01.
For BOM
While creating the production order CO01, system will ask for the BOM selection. Just Ignore the message and you are able to save your order.
Hope this may help
Regards
SS