Romans 10:9: confess 'Jesus is Lord' and believe in your heart that God did what?

Answer: Raised him from the dead

If you confess with your mouth 'Jesus is Lord' and believe in your heart that God raised Him from the dead, you will be saved.

“that if you confess with your mouth, “Jesus is Lord,” and believe in your heart that God raised Him from the dead, you will be saved.”— Romans 10:9 (BSB)