you can add multiple products to the same work order by using the "Product" field on the work order form. Here are the steps to add multiple products to a work order:

1. Go to the Manufacturing module and open the work order you want to add products to.
2. On the work order form, scroll down to the "Products" section.
3. Click on the "Add an item" button to add a new product to the work order.
4. In the "Product" field, select the product you want to add from the dropdown list.
5. Repeat steps 3 and 4 to add additional products to the work order.
6. Once you have added all the products you want, click on the "Save" button to save the work order.

As for changing the name of the Work order, you can do this by clicking on the "Edit" button on the top-right corner of the form and change the name in the "Name" field, then you can save it.

Make sure that you have the right access rights to perform these actions and also check that the production centers are well configured, you should be able to see the products list and the name field.

If you are still facing any issues please provide more details about the error message or what you are trying to do exactly, so I can help you better.