Born in USA of Greek parents Lived in Greece for 7 years and finished elementaty school there
I have my Greek church marriage certificate don't have the baptizmal (lost to a fire ,elderly mom can't remember the church )
Can I apply with this and what else do I need

Efxaristo

Don't worry about your baptismal certificate. What you need is a certificate of registration of your father or your mother [ideally both, but one is enough] in a municipality in Greece. You can either have a relative in Greece pick that up for you, or you can have a Greek consulate do that.

Once you have that certificate, then you will need the following:
1) Your parents' marriage certificate [if they were married before 1982, then it would have to be a marriage certificate from the church]
2) Your own birth certificate certified with an apostille [apostilles are available in every state of the US, you'll need to find out what the state of your birth does]
3) If you are a male under the age of 45, proof that you have been living outside Greece for at least 11 consecutive years until today.

Once you have that, you will go to the nearest Greek Consulate and they will start the process for you. If only one of your parents is registered in Greece, this will take a minimum of 2 years. If both your parents are registered, it will be fairly straight forward.

Hope this works out for you!