These steps are for MT5 on desktop. Menus differ in the web and mobile versions.
Open the Alerts tab in the Toolbox.
Right-click and choose Create, or press Insert.
Choose the instrument, the condition (for example, Bid above a price you set) and the value.
Choose what happens: a sound, an email or a notification to the MT5 app on your phone.
Click OK.
You can also right-click a price level on a chart and choose Alert.
For phone notifications, add the MetaQuotes ID from your MT5 mobile app in MT5's settings. For email alerts, set up your email in MT5's settings first.