Fast and pray , so the Lord will touch his heart to repent, forgive and accept the Lord Jesus as his God and Savior, then during your fasting and praying ask the Lord to reveal you in a dream that your Dad will be with him OR maybe is not his time to go yet, so ask for healing.
God is good and when we obey and humble before Him, he listens our prayers.
I will be praying for you and your Dad.

Have you tried Jesus?
Can you find a christian church in your city? I'm sure the brothers and sisters will reach out to you.
God bless you.