Hello Ishanvi,
Thank you for getting in touch. I will be happy to help.
It involves careful planning the requirements for building an intranet portal using SharePoint in Microsoft 365 include:
Understanding your organizational priorities: You need to understand your key organizational priorities and review your current intranet if you have one.
Planning your SharePoint intranet: Document a vision that will help provide direction and help you prioritize opportunities. Align key outcome goals with SharePoint capabilities to identify where you may need to invest in customization.
Governance: Consider governance processes for provisioning, managing, and maintaining sites and content. Ensure you meet security, retention, or compliance goals2.
Branding and architecture: Decide if all sites should share a common look and feel. Analyze possible opportunities to identify priorities.
IT requirements: IT involvement is required to build and maintain custom solutions, but SharePoint in Microsoft 365 makes it easier to work with responsive, dynamic pages that are easy for anyone to create.
Global considerations: If you’re planning a global intranet, consider hub sites, multilingual sites and pages, regional settings, audience targeting, and Multi-Geo for data residency requirements.
Workflows and permissions: Identify reusable workflows such as manager approvals, understand high-level processes per department, and determine permissions required for each site Please refer to the documentations below for more clarity.
https://learn.microsoft.com/sharepoint/plan-intranet
https://learn.microsoft.com/en-us/sharepoint/set-up-global-intranet
Please do let me know if further assistance is needed.
Kind regards, Adebayo.