1. how do I invest? like what do I use?
You first make a bitcoin wallet. Use Electrum or Exodus. I recommend Exodus because it is monkeyproof and holds multiple cryptos.
https://electrum.org/ &
https://www.exodus.io/ . Take a look around in the Exodus wallet to get yourself familiar with some of the buttons for receiving and sending cryptocurrency. Then you buy BTC from a vendor with USD like you would buy from an online shop like Amazon. You specify how much Bitcoin you want and which address to send it to. If you press receive on Exodus it will give you an address, that's your personal bitcoin address which you will copy and paste on the vendor's website to receive your Bitcoin from. Wait till the next block is confirmed, this may take 15 mins-30 mins and voila there's your bitcoin. Now you can either put it on an exchange like Binance and Bittrex and trade it there for other coins, or just keep it in your wallet. Don't leave your funds too long on an exchange. Oh and you'll probably going to need to verify your ID to trade on an exchange/buy Bitcoin due to increasing regulation. I recommend at this stage you keep it in your wallet and start learning more about Bitcoin and all the other altcoins out there and the problems they are trying to solve, unless you're not interested in long-term investing and purely want to trade.
2. can I use bitcoin money to buy real life stuff?
Some stores accept it, some don't. In Thailand the Dash currency is pretty popular. Also Litecoin.
3.How do I draw back the money into real money?
You sell your Bitcoin back to the vendor you bought it from and they will deposit the money on your bank account.