Yes, salah is obligatory on every mature Muslim; therefore you should start praying salah. Have an estimation of the number of salah missed, then start praying one missed salah with each salah, thus gradually you can perform all the missed prayers. And, when starting the missed prayer, make an intention that you are performing the first or the last missed prayer. May Allah enable us all to pray perfect salah!
Allah (Subhana Wa Ta’ala) knows Best
Darul Uloom Deoband