Do you believe Mary was the Mother of God, AKA Jesus?
Do you believe she is in heaven?
Do you believe Mary can intercede with Jesus on behalf of those who pray to her?
Yes.
Yes, she got there the same way the vast majority do, she died and was buried.
No, 1Tim 2:5 makes that plain, there is one Intercessor between God and man, the man Christ Jesus. Prayer to anyone but God avail nothing.