If you are a big organization with many custom profiles, thousands of users assigned to them, point and click Configuration and customization as required for
Open Activities and Activity History Related List in Lightning Experience
As migrating to Lightning from Classic, You will get confused with the way task, event and log a call are different in Lightning. In Classic,
Lightning Components: how to invoke “New Note” panel from custom components?
You can create your own custom New Note panel which looks better than standard panel provided by Salesforce. Our custom one will come as a
lightning overlayLibrary modal Popup in Lightning Experience
salesforce lightning modal popup