These steps are for MT5 on desktop. Menus differ in the web and mobile versions.
In the Trade tab of the Toolbox, right-click the position and choose Modify or Delete.
Enter the new Stop Loss or Take Profit, as a price or as a distance in points.
Click Modify.
If Show trade levels is turned on in MT5's settings, you can also drag the levels on the chart.
Stop Loss and Take Profit orders are held on our server, so they work even when MT5 is closed. A Stop Loss isn't guaranteed, though: in fast markets or when prices gap, it can be filled at a worse price.
Risk warning: CFDs are complex instruments and come with a high risk of losing money rapidly due to leverage. Only trade with money you can afford to lose.