Chase Sapphire Reserve is offering 50,000 points when you sign up and spend $4,000 in the first three months of opening. That is $500 cash in the form of a statement credit or gift cards or $750 when you redeem through Chase Ultimate Rewards and use your points towards travel expenses such as hotels, rental cars, flights, etc.
On top of that, you will also be reimbursed up to $300 a year for travel expenses charged to your card. Now typically, this comes with a cost of $450 a year as an annual membership fee for having the card, but Chase will waive that fee for Active Duty Military as part of the Military Lending Act perk.
I suggest using the card initially for ordinary everyday expenses such as paying rent, utilities, cell phone bills, etc. to meet that $4,000 spending requirement in the first three months. Be sure to write down everything and keep track of it to not forget to restore your original method of payment after the three months are up. Also, be sure to use the money you would usually use for those bills to pay off the charges to your new credit card immediately. This way, you will not be charged interest, and you don't go spending that money on other items you didn't mean to.
The $4,000 you have to spend is NOT free money in that you have to pay that off. However, the 50,000 points worth at least $500 and the extra $300 a year IS free money. You just need to simply move money around safely and cautiously to receive that free money. If you are not good with credit cards and managing your money, you can easily and quickly find yourself in trouble. Be sure to pay close attention and resist the urge to overspend.
Waiving the $450 annual fee: To waive the fee, you need to let Chase know you are active-duty military. Visit https://www.chase.com/digital/military for directions on providing proof of service.