No way to really guess at it as so many variables.
I'd say figure around 150 between fuel stops, no sense pushing to hard or to close.
That should be a nice 2-3hr ride between fuel stops depending on things like what type roads you take, speed, etc. You can adjust for longer if you want after the first tank and you know a good guess at the MPG of the bike. Not sure what size tank you'll have, but I would guess around high 30mpg and low 40mpg area, and if a 5gal tank that would be a range of about 175-200 miles maybe?
A long ride is about the same as a short ride, but does not end as soon. LOL
What to take?
Are you planning to take 2 or more days to get home, or ride it in 1 day? Makes some difference what to take.
At least one extra change of clothes more than you think you'll need, this is in case your caught in a nasty rain and need to get out of the wet stuff.
Water proof bag for the clothes if not in side bags or trunk, decent garbage bags work great to keep anything dry if the travel bag is not waterproof.
Bungey cords if you'll be carrying stuff on outside of the bike.
RAIN GEAR just in case. If you take it you probably will not need it, if you don't have any then your sure to need it! LOL
If you don't have real rain gear, if needed heavy duty garbage bags and a roll of duct tape works wonders!
Some drinks like Gatoraide or bottled water can be handy. I often get a free ice water at the gas stations or fast food, drink all I want there and take a full one mostly ICE with me when I leave, but it's still handy to have a couple bottles with me if I want to stop middle of nowhere to relax and look at the view.
I've only seen a couple places that charge anything for Ice Water if you have your own cup, 95% or more it's free. Drink lots of water if hot out, and even if not too hot drink a good bit.
Some snack food to munch on is handy also. May plan to eat in restaurants most the trip, but never know when you might want to just kick back and relax 30 minutes or an hour in some really nice place.
Really depends if you plan to just ride home only stopping when needed or make a nice trip of it over a few days.
It's always handy to have other things just in case, but mostly not needed.
Small pack of most needed tools, 12V air compressor, tire plugs if tubeless wheels/tires or patches if tube type spoke wheels.
Most of all travel light!