If the stock I have bought for short term goes up by 5 percent then how do I know when to sell it or keep?

Before making a trade you expect something. So what is your expectations. At which level you think you might have to sell at the time of buying. At that level you should sell.

As per my personal opinion is concerned. I would say wait for the resistance technically. Till that you can wait and enjoy the trend of being right. Bcoz every time you can not make the right trade. If you are into trading, you can make Sense. What I mean. So let's check the levels where is your expectations or find the resistance.

How to find those levels??

Zoom in the charts of 30 mins/days whatever and mark the levels. You can use Fibonacci as well. In case of indicator following, you can see the possible indication through your indicator.

Moreover take advice from the fellow trader/professional. Apart from that, learning begins from questioning. So you did. Make sure you join some group/group of people with similar interests. Meet them and discuss your ideas more in depth.

You can do better in future. Start learning . You will be improve with your understanding.

Good luck