In order to get 50 veil, they need to spend how many coins into the stacking because previously one of my friends send it is going to be more than 10,000 veil in order to get the 50 Veil per day?
You should know that staking is a game of luck. A luckily stakers with their coins used to stake on VEIL network, will fight block and get staking rewards. Basically, the more coins you allocate for each chunk to stake, the more power your chunk has, that in turn will help you have higher probability to fight against other stakers, and the more regularly you will get staking rewards.
This is correct. Generally the more you have staking the higher your odds of getting a staking reward. Right now the estimated amount to get an average 1 stake per day is around 16,000 zerocoin veil.