You are right about several things. You don't know me. The Bible is one way, not the only way, but one way God speaks to us. And that people often filter the Bible to bad effect.
I think you may have agreed with me that the Bible does not teach that I may only belive those things that are specified in Scripture. Scripture does not specify a pattern for how a service of worship was run. Oh a few hints, but nothing like you would even be handed when walking into almost any Protestant c
Service today. And there were reasons for that. They didn't want to commit such important things to paper in an age of persecution. They passed that down orally to those ordained to lead the communities, from apostles to bishops to priests and deacons. It didn't need to be in the Bible what the liturgy was. But when Protestants came along trying to recreate worship by the Bible alone they filtered out the way of worship from the apostles and consequently had to make it up. Not always very well either.
You asked where Purgatory was in the Bible. I might ask where Sacrament or Trinity or Personal Savior are in the Bible. But at least we seem to agree that we are not Bible Only even as we use the Bible as an authority. So, you answered my question and I will answer yours. Purgatory is implied by the Books of Machabees, where some Jewish soldiers are killed in battle and the rest arrange to pray for them, after they were dead. That would make sense with purgatory and would make no sense without it. It's a Biblical instance of the Jewish tradition of praying for the dead.
You might say that isn't Scripture. But Protestants ripped that out because they didn't like the buying and selling of indulgences. They were right about that, as buying and selling of indulgences was a one time mistake by a Catholic violating Catholic rules. But the Protestants went further and threw out indulgences entirely, purgatory entirely, prayers for the dead entirely, and finally started tossing books from the Bible. If Luther had his way you would have a very truncated Bible. Philip Melenchton talked him out of sacking a chunk of the NT.
Christians used the Septuagent from the beginning. And it had all the books. When the canon of Scripture was closed it had all the books. But Judaism decided to close their canon differently. In particular, they wanted to exclude this Jesus the Messiah thing. They couldn't very well exclude Isaiah, but they managed to exclude the whole NT and all those other Greek things, figuring they could exclude Jesus if they only allowed Hebrew in their canon.