You get a 1099R for Distributions. Nothing on the 1099R says if it is the RMD. You have to take the IRA value on the prior year ending balance (so Dec 31, 2021) and use the worksheet to calculate the RMD. Some plans will send you a letter at the beginning on the year to tell you how much to take out. If you have more than 1 IRA you have to figure the RMD on each one but you can take the total out of any of them.
Use this page to determine the RMD (for either age 70 1/2 or 72)
IRA Required Minimum Distribution Worksheet | Internal Revenue Service
