Did Jesus and the other prophets preach that the heavens and the earth were created in 6 days or in billions of years?
This is open to interpretation as previously explained. This depends on what you consider a "day ".
-Some followers of the teachings of Jesus believe the entire universe was created in 7 literal 24 hour earth days with no time passing prior to the first morning.
-Some followers of the teachings of Jesus believe the entire universe was created in 7 literal 24 hour earth days with an unknown amount of time passing prior to the first morning.
-Some followers of the teachings of Jesus believe the entire universe was created in 7 literal 24 hour earth days with billions of years passing prior to the first morning.
-Some followers of the teachings of Jesus believe the entire universe was created in 7 literal 12 hour earth daylight periods between morning and evening with no time passing prior to the first morning.
-Some followers of the teachings of Jesus believe the entire universe was created in 7 literal 12 hour earth daylight periods between morning and evening with an unknown amount of time passing prior to the first morning.
-Some followers of the teachings of Jesus believe the entire universe was created in 7 literal 12 hour earth daylight periods between morning and evening with billions of years passing prior to the first morning.
-Some followers of the teachings of Jesus believe the entire universe was created in 7 creation "days" which are an unknown period of time.
-Some followers of the teachings of Jesus believe the entire universe was created in 7 creation "days" which are billions of years.
Did they preach the earth was flat or a globe?
This is open to interpretation as previously explained. This depends on what you consider "earth".
I would say that a vast majority of the followers of the teachings of Jesus would say the bible says nothing about the planet that we live on being flat.
And did they preach that man was created from clay or that man evolved from apes over millions of years?
Again much of this goes back to the "day" in Genesis. Followers of the teachings of Jesus believe a rainbow of different things. Some believe the bible has similes, metaphors, and parables while some believe that it is 100% literal. If you attend a bible study group these things become great topics of discussion and many times people disagree.
Ultimately, did the prophets preach what the Bible was saying, or did they preach what science was saying at the time?
This also depends on who you ask. Most people who follow the teachings of Jesus would say that the prophets were only preaching the word of God.