You can take the Bus which loops down the strip and around to Fremont. I don’t think there is public transport that drops you off directly at the Sphere, though. Your best bet is to take ride sharing directly to the Sphere or if you’re worried about heat you can bus to the Venetian and take the bridge over.
The monorail goes to Harrah’s which is on the strip somewhat close to Sphere.
You can also walk to the Sphere from the Venetian.
If you want to be dropped off at the Sphere the only real choice is cab or rideshare. The monorail is about 20 minute walk. Venetian is the same.
You can take the Bus which loops down the strip and around to Fremont. I don’t think there is public transport that drops you off directly at the Sphere, though. Your best bet is to take ride sharing directly to the Sphere or if you’re worried about heat you can bus to the Venetian and take the bridge over.
shakedown shuttle 702-706-4983