The values shown are defaults. They can, and in some cases should be changed.
COLA per year: This is the expected Cost Of Living Adjustment average for all the included years.
Monthly amount at 62, etc.: These are the monthly amounts given by the Social Security Administration for each starting age, which can be obtained by logging onto the SSA website at https://www.ssa.gov. You really shouldn't trust me and log on after clicking this link, but you can if you want to. If you enter the first amount (for age 62) and tab off of the field, it will prompt you to let it automatically fill in the other values for the rest of the years from the percentages provided by the SSA. Or you can enter those other values yourself to override the defaults. The percentages were obtained from a 3rd party and they don't appear to be quite correct. You should override the defaults for more accurate results.
Expected end of life age: Enter the age that you expect to stop receiving Social Security benefits.
Submit: Click the Submit button when you have entered all the values, and the results list will fill with the calculated total amounts for each of the ages that you can start receiving benefits.
Results List: When you click the Submit button and the results are shown, you can expand and collapse the detail subdivisions for the given starting age, so you can see the details for each month.
The results assume that you spend all the money immediately, rather than saving some or all for the future. You will need to calculate any saving manually.
The actual COLA percentages vary every year. They can be obtained from https://www.ssa.gov/cola/
One huge takeaway from this is: if you want to double the monthly amount that you receive, you should amass the Total amount in your own savings BEFORE retiring. (ouch!)
An even bigger takeaway is that you should invest any surplus amount in such a way that you are beating inflation, such as a high yield bond fund or something more risky.
Of course politicians are at best powerless to preserve social security, and at worst actively trying to sabotage it for their own agendas. Make sure to vote to oppose this. Question: do politicians lie and say they want to preserve SS? Which ones?