https://www.blueletterbible.org/faq/don_stewart/don_stewart_739.cfm
Above is a link to an article with the various verses where the writer pins it down to 371 days. There are other folks that count things a bit differently (letting the birds out for 7 days, did Noah release the next bird that same day or the following day, etc.) but all close to that number.
But for a general idea based on the verses the flood began when Noah was 600 years old and they left the ark when he was 601 years old. Hmm, even if it took 30 years for the water level to get back to normal that would be like 3 years in “our time” (Noah lived to 950 years, say 10 times our lifespan if you are lucky).
In the six hundredth year of Noah’s life, in the second month, the seventeenth day of the month, on that day all the fountains of the great deep were broken up, and the windows of heaven were opened (Genesis 7:11).
And it came to pass in the six hundredth and first year, in the first month, the first day of the month, the waters were dried up from off the earth: and Noah removed the covering of the ark, and looked, and, behold, the face of the ground was dry.
And in the second month, on the seven and twentieth day of the month, was the earth dried. And God spake unto Noah, saying, “Go forth of the ark, thou, and thy wife, and thy sons, and thy sons’ wives with thee.”
(Genesis 8:13-16).