This is a loaded question that took me a lot of critical thinking before I could give my own thoughts about it, am I'm sure everyone thought will be indifferent about it because of our different perspective.
WHAT IS DESTINY
The dictionary defines it as the predetermined, usually inevitable or irresistible, course of event while some will say it is what you are ordained to be in life or on the other hand, it is your expected end. Personally I think when we talk about destiny, you can also view it as fulfilling a purpose. Religious or not, most people want to believe they have a purpose for living.
We all believe that every one created by God as a purpose here on earth which implies to as fulfilling destiny. Nothing can change the fact that we all humans have a unique reason for being here.
For instance, let's look at it from a Christian view, God has a prearranged plan for each one of us, starting from the creation of earth, The Book of Genesis(book of creation) talks about how God made an indescribably glorious world in preparation for man's coming, He created all what man needed before him on the sixth day, He didn't just create him in his own image alone but also positions man in the garden of bliss to fulfill his purpose or destiny. This really shows how God works, He didn't just create humans to be fruitful and replenish the earth but also to fulfill the purpose which he designed us to do, in which most of us haven't discovered yet.
Jeremiah.1:5
God said to Jeremiah, “Before I formed you in the womb I knew you; before you were born I sanctified you; I ordained you a prophet to the nations” This scripture in the bible talks about a servant of God in the bible Jeremiah who God himself as ordained to be a prophet before he was even born, for him to be chosen by the one who gives life shows every being he created have a purpose or destiny to fulfill here on earth. And also that part of the bible made us to understand God has written something for every man before he was born. This life is more like a movie, we all have our role to play.
KARMA
Do i believe in karma? Absolutely yes
“Karma” simply means action also it means that everything that happens is a result of things which you have done in the past.
This doesn't have to be maybe you are spiritual or not, its just how this world is designed.
There is this saying what goes come around, There are rewards for every action you make. For instance, there is this man in the bible Jonathan king Saúl's eldest son, Jonathan was a man of honor, courage and wisdom, which also his heart is full of love. The story of Jonathan and David told in the bible tells how Jonathan went to great length to protect David from his father king Saúl from killing him in other for David not fulfil the purpose which God wants him to. Jonathan passed away and as well king Saúl and David was crowned. But the good deed of Jonathan made mephibosheth Jonathan's son who was a cripple find favor in David's sight.(2 Samuel 9:3) David sent for Mephibosheth, Jonathan's son, so he could, “show the kindness of God to him”. God not only counts every good deed a person does, He multiplies it and rewards them, so as the bad deed as well.
So i believe destiny and karma is real