Scientists agree the universe is 13.8 billion years old, keep in mind the number has been revised many times...There is data that the universe could be older than 14 billion years old! Any scientist with an open mind would recognize there are areas of the universe we have tried to study that we cannot see. A lot of things in the universe (galaxies, planets, stars etc...) are blocking light from getting through to us to see, we are not getting the full picture of the universe, that should be enough for people to admit we don't know for sure, but there is more data suggesting the universe could be older than 13.8 billion years. There is a star called HD 140283 it's one of the most studied stars which can be seen with binoculars as a 7th-magnitude object in the constellation Libra. NASA says "The star could be as old as 14.5 billion years (plus or minus 0.8 billion years)," the big bang theory says the universe was too hot for stars to form during the first few hundred million years, which puts HD 140283 right at an age where it provides further scientific evidence that the universe could be older than 13.8 billion years!

Lets assume HD 140283 is the minimum age 14.5-0.8=13.7 billion years, according to the big bang theory we shouldn't see any stars form until 13.4-13.5 billion years, 13.6 being extra considerate because a few hundred suggests over 200-300. Math shows the universe must be older than 13.8 billion years, if HD 140283 is 13.8 billion years, according to big bang theory the universe must be at least 14 billion years of age, not 13.8.

As more progress is made in science over the coming centuries, it's possible scientists will discover stars that pre-date HD 140283. One day people will realize some of what's written in school textbooks has been proven wrong, now you know why some people compare mainstream science to religion, both based on belief systems. The big bang theory has done good for human civilization got us this far, we shouldn't be afraid of information that proves the big bang theory has flaws, we shouldn't be afraid to try and seek alternative answers. The education system does not teach people to be open minded scientists, in fact people get rewarded for doing what they are told in the education system, the big bang is taught as fact, if I wanted to work at NASA (my dream job when I was a kid) I would have to write in school exams and tests whatever the mainstream theories are and if I write the correct answers I fail the tests and can't work at NASA!

Reference: Hubble Finds Birth Certificate of Oldest Known Star https://www.nasa.gov/mission_pages/hubble/science/hd140283.html