Add the Flow component to your Lightning Pages just like you would any other component.
Your flow might need the ID of the record that it’s operating on, but don’t worry! When you configure the Flow component for a Record page, you can identify to which Text variable to pass the record ID.
Here’s how a flow called Survey Customers appears when embedded in a Record page in Lightning Experience.
Changes Since Last Release
We changed how you pass the record ID from a Record page into a flow. Previously, you configured a variable with a specific name. Now you can pass the record ID to any Text variable, no matter what your naming convention is. To do so, select the checkbox under the appropriate Text variable.
If you created a Text input variable called recordId for the flow component during Winter ’17, the checkbox is automatically selected when your org upgrades to Spring ’17. This default selection happens only when your org upgrades to Spring ’17. If you create a Text variable called recordId in Spring ’17 or later, the checkbox is not selected by default.