Who is the 1st teerthankar
The 1st Tirthankara is Rishabhanatha, also known as Adinath. He is regarded as the first Tirthankar who established Jain Dharma in the current cosmic era (the present half-cycle, known as the avasarpini). In both Digambara and Śvetāmbara traditions, Rishabhanatha is honored as the founder of the Jain path, though there may be some tradition-specific stories about his life and deeds.