How to Show a set fields only in Lightning Experience without code?

Business requirement:- 

Your users want you to show a particular set of fields only in Lightning Experience but not in Classic Interface. Those fields are not required for classic Users. Also, Using Lightning Component is not recommended as it will impact the page performance and looking for point and click solution in Salesforce.

Solution:-

To achieve the above ask, Salesforce provides us a standard Lightning Component called Related Record which comes to rescue you in this situation.

Use the Related Record component to display the details of a related record, including the details of a parent record in your Lightning page. This component provides your users with built-in record creation, inline edit, and the ability to unlink a record and link a new one. This functionality is possible because the component uses actions. This component is supported in API version 39.0 and later. You can use it only in record pages.

Steps to follow:- 

1. Create an action of type update on your object
2. Add the desired field on your update action layout
3. Save your action and navigate to object record page
4. Click on setup and select edit page
5. In left side pane of Lightning App Builder, search for related record, select and drag it to the canvas where ever you want it.  In left hand side, select your action in update action property.
6. Save your page and click on back. It will navigate you to record page. Let’s see what we have done.
7. If you notice, Fields(type, Phone, Website, Industry) are available in Lightning but not in Classic.

Note 

Keep these considerations in mind when using the Related Record component.

• To use the component, an object must have an associated quick action to update the records. Some lookup fields have default actions. If no actions are available for your lookup, follow the links in the Lightning App Builder property editor to create the actions.
• To change the displayed fields for the Related Record component, customize the associated action in Setup. If you don’t see the action or can’t modify it, create a new one. Also, ensure that the lookup field to the related object is included on the page layout of the main object, otherwise the component can’t be refreshed.
• To use the Parent Case and Asset lookup fields on cases, change the field-level security to visible instead of hidden. Otherwise, your users see an error.
• Person account records that display in contact Related Record components are read-only.
• Cases are linked to default accounts that can’t be removed (unlinked) from the component unless the contact is also removed at the same time.
• The Related Record component typically uses quick action metadata to determine which fields to show. However, if the user viewing the component has read-only access to the related record, a compact layout is used to render the fields instead. As a result, a read-only user sees a smaller set of fields.