When I first started learning about stock markets I got a lot of insight from one comment a friend (who had gone into finance) made to me: the stock market is not a vending machine.
There is no set price to buy shares. If you just want to buy 100 shares at the current ask, it'll probably go through (but even that is no guarantee), but the next 100 shares might well not be available at that price anymore.
There is no set price to buy shares. If you just want to buy 100 shares at the current ask, it'll probably go through (but even that is no guarantee), but the next 100 shares might well not be available at that price anymore.