Assuming you mean US Social Security, you could have started payments at age 62, at reduced benefits. You could have waited until age 67, to get nominal full benefits. You could wait until you turn 70, to get the maximum benefits. Or any point between those, with benefits intermediate between those values. I’m not sure what the formula is for the reductions if you start early, but after age 67 the growth is theoretically roughly equivalent to if you were investing the payments at an 8% rate of return — not hugely exciting, but it is guaranteed. Assuming you and the program both survive that long.
Since you are about to turn 70, if you are in good health I would normally say you might as well wait to start the benefits until your birthday or shortly thereafter, to get the maximum payment.
On the other hand, these are not normal times in the United States. I honestly do not trust this administration not to try to kill or reduce Social Security. As a result, I decided to start Social Security this year, on the principle that getting less beats getting nothing. That may not be reasonable, but neither is the situation.
Addendum, thanks @MTA: Note that you don’t necessarily need to wait before submitting the form:
Applicants may apply not more than 4 months before or 6 months after their desired starting date for Social Security benefits. When applying after, SSA will pay retroactive benefits, but no more than 6 months’ worth.
From ssa.gov/pubs/EN-05-10377.pdf