Redeeming airline miles is usually pretty simple. With most airlines, you can redeem your miles for a free flight by logging into your account during the booking process. You'll need to book on the airline's website, rather than travel websites such as Expedia or Kayak, if you want to pay with miles.
If you have already flown and have not received mileage credit, you must make a retroactive claim directly with your frequent flyer program. Please check your program's website for the complete details on how to file a claim. Please allow 14 days from the date of your flight for the miles to be posted to your account.
Our new valuation pegs United miles at 1.1 cents apiece, so 30,000 miles are worth $330. Naturally, the value of your miles can vary, but you should aim to get around $330 in value from these United miles.
With 80,000 United miles in your MileagePlus account from the United Club Infinite Card, you could fly yourself from the US to Europe on a round-trip ticket and just pay the taxes and fees out of pocket.