Can a Rebel 250 handle The Loneliest Highway?

I have a Honda Rebel 250 and want to know if it can handle the inclines on US route 50 from Ely to Carson City Nevada

Added (1). I forgot to mention that I would be riding with a couple others, and we would have a chase vehicle with supplies such as food, water, and fuel

That's not to extreme for a REBEL unless it's overloaded.

It'll handle anything, but accept you will have reduced performance if you are a big guy, heavily loaded, headwind, passenger etc…

Hell, if I can drive up and down the Adirondack Mountains in a 1982 Subaru hatchback loaded with my luggage and almost every tool I owned you can do it on that bike. I'd recommend bring some survival supplies including a minimal tool kit, rain poncho, pup tent water filter (hiking style, like a Katahdin, not a Britta) and survival tabs. I envy you. Watch out for cages.

I rode a Honda CB 125 from Los Angeles to Salt Lake City (700 miles of I-15) back in 1978.

There are not a lot of really steep inclines on Hwy 50. Depending on the load you're carrying, the Rebel 250 can run all day at 65-70 miles per hour, but I don't think it has enough fuel capacity to run the 300+ miles of highway between Ely and Carson City. Plan your trip carefully and stop for gas whenever it's available.

Heard of gears? Like wow.

It and you both can, just don't expect riding the speed limit in the mountains. Use the gears in the transmission, plus get fuel at every opportunity, keep hydrated, and you'll fine.