Your financial institution should be able to give you that information.
Please be aware, if you had the Roth IRA for 5 years and are over 59 1/2 then you getting Qualified Distributions which are nontaxable and you will not need to know the total contribution (you can ignore the net contribution question in TurboTax). Your Form 1099-R will have code T or code Q.
Otherwise, you will need to check your documents or ask your financial institution as Bsch4477 mentions.
I took money out of my Roth in 2022. Then TurboTax asked me if I took anything out before then, which I did once in 2019. Then it asked me what my NET total contributions were and I have to answer that question as I don't see any way out. Do I go back and tell it I never took any money out? I've had this Roth over 20 years and I will be taking money out in the future too. What do I do?