chore: Update introduction and getting started sections

[neelanjan00]

What this PR does / why we need it: Updates introduction and getting started sections

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #

Special notes for your reviewer:

Checklist:

• [ ] Fixes #
• [ ] Signed the commit for DCO to be passed
• [ ] Labelled this PR & related issue with documentation tag

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Name	Status	Preview	Comments	Updated (UTC)
litmus-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Sep 29, 2023 0:37am

[SahilKr24]

please run this though grammarly once

[Saranya-jena]

Build is failing, can you build it locally?