A good option for you can be a credit card with miles rewards issued by a major bank. Such cards often come without an annual fee, a perfect option if you want to keep the card for a long time and as a primary card. Then comes the rewards program. You will be able to earn miles on all purchases and then redeem them with any airline of your choice or for any travel expenses. You won’t have to travel to earn miles, you can simply shop as you always do and earn miles towards your future travels. Earned miles do not expire and you can earn as many miles as you want.