The notifications feature is available under the Notify tab of your chosen protocol, where you can configure both wanted monitors and delivery channels.
Assuming, for example, that you have a position in Aave v3 that you want to enable notifications for, you would navigate to the Aave v3 dashboard, then make sure that you have the correct position selected (Account or Smart Wallet) and finally switch to the Notify tab in the top navigation.
Once there, you'll see this screen:
Clicking the Ratio Monitor box will pop up a window that allows you to set up a ratio based trigger for notifications, where you can select whether you want to be notified once your ratio drops below a certain ratio or once it raises above it.
Once you have your wanted monitor set up, you will also want to configure the channels of delivery.
The Manage channels button will bring up a window that lets you configure different options for notifications delivery, including Telegram and Email.
All enabled notification monitors and channels can be disabled by the user at any wanted point in time.