Using List Button and Flow URL, we can invoke the Flow from related list Button in Salesforce Lightning Experience. Please check the following with the Steps.
1. Create a Flow.
2. Get the Flow URL.
3. Create a List Button with URL and use the Flow URL.
4. Add the List Button to the related list in the Parent object page layout.
![](https://www.infallibletechie.com/wp-content/uploads/2020/03/Adding2BRelated2BList2BButton2Bin2BSalesforce2BLightning.jpg)
Output:
![](https://www.infallibletechie.com/wp-content/uploads/2020/03/Related2BList2BButton2Bin2BSalesforce2BLightning.jpg)