In this blog, I would like to discuss you about how to create a custom lightning page template or layout using SFDX.

Create Lightning component
Lightning component resides inside a lightning project so create a project and follow the below steps. If you are not aware of project creation then go through my blog.
- Create a lightning component in Visual Studio Code
- sfdx force:lightning:component:create -n <component name> -d <location>
- Modify the design page to show the custom attribute in the layout selection or page layout editor


Push Code into scratch Org
- Create a scratch org
- sfdx force:org:create -s -f config/project-scratch-def.json -a <alias name>
- List all connected orgs including scratch org with Visual Studio Code
- sfdx force:org:list –all
- finally, push the code into scratch org created

Create a page named My Bike in the Lightning App Builder.
- Go to setup –> Lightning App Builder -> New

- Select App Page in the options
- Then, fill the field with your Page name and click Next

- Select your custom or standard layout
- Our custom three column layout displayed under Custom section

- Then, Click Finish button to include the custom or standard component in the layout

- Click Save and Activate your page to the preferred profiles and apps
https://developer.salesforce.com/docs/component-library/bundle/lightning:appHomeTemplate
Each template component should implement only one template interface. Template components shouldn’t implement any other type of interface, such as
flexipage:availableForAllPageTypes
or
force:hasRecordId
. A template component can’t multi-task as a regular Lightning component. It’s either a template, or it’s not.