What do I do with a plane itinerary?

So a bit of context:

I'm flying domestically to Job Corps and they sent me this plane ticket itinerary detailing the flight. This whole time, I was lead to believe that they would give me an actual plane ticket, but instead, they've emailed me and told me to print it out. Do I go to the airport now or something to redeem it as a plane ticket or do I wait until the day I leave? There's no barcode.

Also, there's a second part where it says:

Prepare Part II for each student when transportation is furnished for home leave, emergency travel, or upon termination and return to home of record. I hereby acknowledge receipt of taxable transportation (FICA and Federal Income Tax) furnished to me for ___ Leave, ___ Emergency Leave, or ___ Travel to home of record upon termination, valued at $__________. I understand these taxes will be withheld from my semi-monthly allowance until paid. I also acknowledge that if a ticket is ordered for me I'm responsible for the cost of the ticket if I'm in an unpaid status. Additional fees may be charged if you plan to check one or more bags or if your bag exceeds the carrier s weight and/or size limits. Collection of these fees, if applicable will be made at time of passenger check-in. ___ RT ___ OW ___ Meals ___Student Signature / Date

I would just print it out and then they'll give you your boarding pass

Your printout is an eticket, you scan it at the airport to check in for the flight.

There have not been paper tickets for airlines for several years now. Just check in for the flight using the confirmation number on what they sent you and you can print the boarding pass for your fight. You can do this at home (using the airline's website) or at the airline check in counter at the airport.

You are getting what's called a PTA(Prepaid Ticket Advice)
so print out the itineray, and head for the airport
with some ID
at check-in you will get your boarding card
no need to worry its all in the airline computers

There are no paper tickets issued anymore. Tickets are electronic, and what you received is the equivalent of the ticket. Print it out and take it to the airport with appropriate ID for flying. They will give you a boarding pass, which is what you need to get through security and onto the plane.

There's no physical ticket to get. Hasn't been for years.

You print out the ticket. Also take a photo of it with your cellphone cam to have with you. There should be a bar code or set of numbers on it or both. Once at the airport you put those numbers in the machine there or scan the bar code. It prints you out a ticket. Or stand in line at the counter & they will do it there. Then go to boarding area. It should also have a gate number. Go to that area to do this. Recently at a local airport over seas I went to a counter with my print out & the girl could not read English. But had mastered the same from a cell phone image & got my ticket. Don't ask me the why of that as they were the same.

The physical plane tickets went the way of the Dodo bird decades ago. The itinerary they sent you is all you need. Just show up at the check in counter with a proper ID before your flight and you'll get your boarding pass. You can also check in for your flight up to 24 hours before your flight on your computer. You will need a confirmation number from your itinerary to do that and then you can print your boarding pass at home. Then, when you show up at the airport, just drop your bags at the luggage drop off and go straight to security checkpoint.

Strictly speaking you don't even need to bring the hard copy of the itinerary with you. It's there just for your information.