Your Roth IRA can't be 30 years old since Roth IRAs were not available before 1998. Still, I'll assume that your first Roth IRA contribution was made before 2020.
If you were over age 59½ in 2024, there is no real need to know your basis in Roth IRA contributions and conversions because any distribution from your Roth IRAs would be qualified distributions and Part III of Form 8606 should not be prepared.
