Each tunnel is less than half a mile long. So one tunnel will take you there and one will bring you back
How fast is this supposed to go? Assuming the station is in the middle that's only 683.5m between them, and the whole thing is only about 1350m long. To get up to the high speeds they were talking about the acceleration would have to be pretty extreme. Not very comfortable for the passengers.
System expansion to two hotels approved by the county: Elon Musk's Boring Company gets green light to expand Las Vegas Loop with Tesla vehicles - Electrek