I have some 100 shares of a reputed company since 3 months. The share price is fluctuating every day. sometime price go low in the morning and high in the afternoon again low or high and so on. If I sell the shares when it reach high in any point of the day, will i get the share value at that time I sold i.e. at peak or it is the value of the share at the end of the day value.
You will get the share value at the time you sold, not the price at end of day.
For shares in a company, the order executes at whatever market price is in effect at the moment the shares are sold. This is called a Market Order. You can also set your own price (a Limit Order) and the shares will sell when and if a buyer can be found at that price.
For mutual funds, the order is executed at the next closing price. So on a trading day, the shares are sold at that day's closing price.