Hi
For this there is a lot of work and configuration to do so it can not be done ery urgently Image may be NSFW.
Clik here to view.
You have to follow third party sale concept and modify the process as per your requirement.
Create STR automatically by configuring the schedule line in VOV6.
Assign this schedule line category to your item category.
When you save sale order an STR will be saved automatically.
Create STO in ME21N and delivery in VL10B.
Create GRN in MIGO.
Create delivery w.r.t sale order and invoice.
This will be the process and if I have missed something then you can ask. There are lot of discussions on STO configuration which you can study and follow.
Thank$
