Yes it is possible, just like driving a car with your feet is possible. That doesn't make it wise though.
For example, simply post a thread here and offer to give anyone who posts a message an initial share of the coins. There are many other ways to do it, all as equally useless. What is not earned is not appreciated.
If you mean, can you have a consensus algorithm based on how many coins each person has without anyone initially having coins.... well that's obviously a no. This is why you need that proof-of-work period at the beginning.
Great answer so you will need first need to implement a proof of work before you make a shift to pos
but for example the supply is 100 million and you shift to pos but the only coin that was mined from pow is only 20 million can the 80 million left be mine by pos..