How to heal from death of a parent ?

It takes time, some never heal completely.

Eventually the pain of the loss fades and you can remember the good times with your parent, the happier moments in life.  Pictures bring back happy memories not painful ones.

Be patient with yourself.

Time heals all wounds.

Jesus said we are all God's in John 10:34.  We are here to grow to perfection . No excuse or sorrow felt from God.

It was once asked was the chicken or the egg first. It is true the chicken comes from a egg but we must go to the very beginning for the answer. A hen can have an egg without a rooster but it will never hatch needs fertilized so no matter how you look at it the chicken was always before the egg. The rooster had to be here to start the fertilized egg and he needed the hen to do that. From that point on the egg was after the chicken. It took two adults to have a baby but the first two humans were never a baby in this world you need developed thought to care for and raise a baby or to have one. Females in a coma have had children from males with knowledge of what he was doing but one had knowledge. It all leads to word was first and we all live in word so your parent is only gone in body . God is word and word lives or nothing would exist. or https://futurism.com/the-physics-of-death

First and foremost, I want to say that I am so sorry for your loss. One of the saddest and most devastating things we endure as humans is the loss of a loved one. 

But there is a promise to us from God at Revelation 21:4. It states "And he will wipe out every tear from their eyes, and death will be no more, neither will mourning nor outcry nor pain be anymore. The former things have passed away." 

As we await the day when God will rid the earth of death, what can we do to cope with the devastating effects of loss? The following link takes you to an article entitled Coping With Grief - What You Can Do Today: https://www.jw.org/en/library/magazines/awake-no3-... I hope you can gain some comfort from this article.

Luke 9:59-60 

And he said unto another, Follow me. But he said, Lord, suffer me first to go and bury my father. [60] Jesus said unto him, Let the dead bury their dead: but go thou and preach the kingdom of God.

Psalm 27:10 

When my father and my mother forsake me, then the Lord will take me up.

 To grin and bear it.... My father is currently dying in a care home in England. And because I currently live in Germany im not allowed due to the current covid restrictions in force to even fly there to see and hold him one last time..... That deeply hurts me.

Sorry to read of your recent loss.... I´m gonna be in the same boat soon and I wont be able even to attend his funeral as things presently are sadly

You do what is right in your life, then go to the next thing. Don't sit around and be miserable if you can help it. Just do what you normally do. It's brave and healthy. 

Practicing Christians believe the verse at Acts 24:15, which brings great comfort. "And I have hope toward God, which hope these men also look forward to, that there is going to be a resurrection of both the righteous and the unrighteous."

We know the dead rest in God's memory and he longs to bring them back to life at an appointed time. See the link below.

You don't ever completely "heal" the pain becomes less with time