Idk why someone said more, no more information is needed. Everything is outlined in the question as needed. AGAIN, read the question, please. The question is to "Draw a sequence diagram from this use case description (aka the description above).

From the following description, describe the use cases, by identifying the actors, basic course of events and possible alternatives: The PSL company has a website allowing online orders to buy Pizzas, Sandwiches, or Lasagna in the Lamar University campus. A customer can either walk-in at PSL to buy meals or he/she can make online orders using the PSL website. Either way, after selecting his/her choices and doing the payment, the PSL acknowledge order delivering the meals and the receipt. Draw a sequence diagram realized from this use case description