There’s a distinction here between Buddhas and “wheel turning Buddhas” - wheel turning means that they teach the path to awakening when it has been totally forgotten. The Buddhist sutras say that Buddha was the fourth of a thousand wheel turning Buddhas in our world system. Each one teaches, the teachings last for a few thousand years, then fade away and get forgotten. There’s then a gap with no teachings, then a new Buddha arises.

In the sutras there’s a passage about how after Buddha became enlightened, he was unsure whether to teach, wondering whether anyone would understand his teaching. He got persuaded that there are a few with “not much dust in their eyes” who would understand.

So - there’s the idea there that Buddhas can’t teach unless they are invited, so in that case it was Brahma Sahampati who asked Buddha Shakyamuni to teach in the Buddhist mythology about how the teachings got started: Ayacana Sutta: The Request

Awakening anyway is a natural thing, you don’t have to be Buddhist to awaken. so there may also be beings who awaken in between the wheel turning Buddhas when there are no teachings available, but if so, they are not able to pass on the teachings to others, at least not in the complete way that wheel turning Buddhas do, by setting up a tradition with complete teachings of the path for all types of beings.

In the Bon tradition in Tibet they claim that their teachings come from the third Buddha in our world system, from many thousands of years before the historical Shakyamuni Buddha.

Historically, there’s the one wheel turning Buddha in the early sutras in the Pali canon, but he had many followers who became arhats. This also is just one world system of many. In the Mahayana teachings especially they talk about countless Buddhas.

So anyway - that’s the traditional view on this matter. They also talk in detail about many different types of “awakening” and make a distinction between arhats, pratyekabuddhas (who become enlightened at times when there is no wheel turning Buddha’s teachings available), boddhisattvas and so on.

I think there’s also quite a bit of variety between the different Buddhist traditions on how they understand all this. And some of the traditions also teach that everyone is already enlightened if one can but see it (in those traditions, then enlightenment also involves not being caught up in rigid concepts about time and space). They also say that it is easier to be enlightened than unenlightened, and that most beings are enlightened already - we are just the few who somehow haven’t “got it” yet.

This is just a brief introduction, I’m not expert on this, but hopefully that’s a few pointers that may be useful.