The Order Form checkout will handle shipping automatically.
Multiple Shipping Options
Shipping dropdown will appear at the bottom of order form if multiple shipping rates are available for ordered product:
The purchase total will change when different shipping option is selected.
One Shipping Option
If only one shipping option is defined for selected product the order form will show its value and will calculate the purchase total accordingly:
Shipping in notification emails
Selected shipping method along with the cost is included in notification emails.
Shipping cost in payment gateway
Shipping cost is passed to selected payment gateway if any gateway is enabled.