Do I have a chance to get British Citizenship?

Hi, please help me.

I'm from Poland, but I moved to UK when I was 9 and went to school here. I finished 6th form in June 2015, then I got job in august 2015 and worked there until december 2015. I was jobless until may 2017 and worked there until august 2017. Then I moved to Poland and came back and started work in november 2018 and I've been still working there. I want to apply for british citizenship but I worry about the time I was jobless because I wasn't signed up in jobcenter or have any proof I was here (I live with parents). Will I get refused even if I'm living here since young years?

Do you have a document certifying permanent residence or Settled Status granted under Appendix EU??

You probably acquired PR while you were at school. You will have clocked up the 5 years residence for the settlement scheme while you were at school. Since you left school, there have been no gaps of 2 years or more, so your only problem should be to prove that you were resident while you were at school.

Trying to get EU settlement status should be a good start, as it is relatively easy and free. After one year, you can apply for the UK citizenship.