Creating Invoice and Package from sales order API

Creating Invoice and Package from sales order API

Hey there,

I simply need a way to create an invoice and package from a sales order. 

I tried already the API endpoint "invoices/fromsalesorder" but using this is always chaning my sales order status to "fulfilled".

How can I solve that?
Can I manually change the status or conntect invoices/packages with sales orders?
Is there a way to create a package from a sales order, too?

Thanks for your help