Most restaurants choose to have their customers transferred from their website to Online ordering page (using Direct link to delivery/pickup page).
Options to choose between:
As soon as possible
Schedule for later
After that, customer should choose items from the menu.
Then, customer should:
enter contact information
take a second look at the order
decide on the tip amount
decide on the type of payment (pay cash, by card or by invoice)
click on "Complete order"
You can also have online ordering widget on your website or on your Public page.
Guests would go through same steps as mentioned above.