HI, Glad you made it to the trading world! Basically I believe you are referring to market manipulation. The best answer to your question is “it depends.”
Where are you trying to do this? If your in Jita, Sure you can do this but people will see the price gap change and want a piece of the pie and it will very quickly get back down to a normal price so you will still have a lot of competition. If your doing it not in a trade hub, you might have better luck but you still have volume to worry about there.
What kind of volume does the item usually have? More volume it has, the easier it is going to be to sell it at a higher price but that generally is going to cost more to manipulate the price to get that gap which bring me to my next point.
How much capital do you have? Generally something like this to be successful, requires a lot of capital and also come with a lot more risk.
Conclusion: There is plenty more question/complication that can arise when trying to manipulate the market, and this I would consider to be one of the hardest one to put off the be successful. You have to find the right item at the right time in the right place. It can work, but you need to know what you are doing and what the market is doing. My advise is stay away from this until you get your feet wet.
Good Luck and hope you make a ton of isk.