Flexible Spending is away to build up funds for medical expense. You can elect for an amount to be taken out of your pay check before taxes are applied and put them on your FSA Card. At the beginning of the year you would elect how much money you want to contribute a month. Once you receive your card it will have the balance of your monthly contribution times twelve. So, all the money you will apply throughout the year will be available immediately to use towards your current and future medical expense.
This is a program where you will need to plan how much you will spend this coming year. The 2020/21 annual maximum contribution is $2750.