Custom Lightning page template components let you create page templates to fit your business needs with the structure and components that you define. Every standard Lightning page is associated with a default template component, which defines the page’s regions and what components the page includes. You have to create custom page layout using Custom Lightning Component. What should i do if i have to accommodate more than 25 components in Header section of the Lightning Page? Also, it is not advised to have that much component on your page because of page performance issue. We all know, in very rare scenario, We have to add more than 75 components on a single Page. So, If you have selected Header and Left Sidebar as page region, You cannot add more than 75 component on your page. Salesforce allows 25 components to be accommodated in each of the section you have in your Lightning App Builder Canvas. The question here is how many components you can add in each of three section on your lightning page?

For e.g If you have selected Region as Header and Left Sidebar, you have three section where you can put your components. Once you have selected a layout with you want to proceed further, You can add Components in the section. Whenever you are going to create them, You have the ability to select the layout structure of the Page. You can create three types of page in Lightning i.e Home Page, Record Page and App Page. You may be wondering about the limit Salesforce put while creating lightning page using Lightning App Builder.

How to open lightning app builder