Let me just supplement UH's answer on Average True Range. ATR is the average distance between the high for the day and the low for the day over a 14 day period (the days are of course adjustable). In short the daily trading range from hi to lo expressed in $ which for stop loss purposes may be converted into a percentage if you wish.

Thus by setting your stop loss within the typical daily range you almost guarantee the stop loss will be triggered quickly. Go ahead and try it if you want to do so. Consider it tuition if you get stopped out quickly.

I second the motion that you need to get access to some decent charting and technical analysis software if you are going to use these tools. Even with the stuff you are going against computers programmed with AI that makes trading decisions in seconds without a human in the loop. Today's trading volume is heavily computer driven and without decent analysis software it is like flying a Sopwith Camel into a dogfight with an F-15. The odds are very bad for you.

Apologies to others for the technical discussion.