Rishabdev (Adinath) is considered the first Tirthankar in Jainism. Because he is the first Tirthankar, there are no preceding “bhavs” (previous births) for him in the canonical Jain chronology. The tradition describes his life as the starting point of the current cosmic cycle, after which 23 more Tirthankaras arise in succession.

If you meant a different topic by “previous bhavs” (for example, the lifetimes of a specific Jina or a posthumous lineage in a particular text), please tell me the exact context and I’ll explain according to Jain sources.