Last things first.
Nobody is going to pay you to ride across the country.
I have planned and implemented a major fundraiser -
And you could earn more money working a minimum-wage job for the hours put in.
I've ridden 100,000 miles and have seen all types of bicycles and riders.
You don't have to have all the bells and whistles - although decent basics are the core.
There's nothing worse than biting off more than you can chew -
The Western Express is pretty unforgiving - esp. for a newbie.
Don't know where you're from but you have the Sierra Nevadas to climb -
then the huge empty stretches of the Nevada and Utah deserts.
If you are looking to make a shorter trip than the full TransAm -
consider cutting through Idaho from Ontario, OR via Stanley, ID to Jackson, WY.
You could get your "legs" using ACA maps at first - then branch out on your own.
From central Wyo, you might consider crossing Nebraska and the Midwest -
rather than the TransAm route thru Kansas, Missouri, and Kentucky.
There is no law saying you have to stick to mapped route - make your own.
Plus you'll be a good bit cooler in July in northern Indiana than in Kentucky.