Best way to build a Social Media Platform

Hello Everyone,
I am a fullstack dev and wanted to build a social media platform to explore the possibilities with different databases :upside_down_face:
But I am really struggling to decide what should be the best database or databases to implement all these features like:

  • Community detection
  • Trend detection (last year, month, week, day, 7hours, 15mn)
    — trending categories
    — trending posts
  • Counters
    — total users
    — total friends
    — total posts and total per user
    — total comments etc…
  • Search engine
    — search users / posts / categories (with trending ones at the top)

I understand that Graphdb are perfect for community detection but not for trend detections where time series db seems more adequate.
For the search feature I am not sure what to use to be able to search any keywords like name, lastname, posts, categories or even the content of a post.

The idea is to design it and test for 10 million users posting 10 posts a day each (at least :stuck_out_tongue_closed_eyes:)

Will you use only 1 database to achieve all that or will you use different databases and connect them together to get the best from all ?

Could you guys tell me what you will use to cover each of these feature please ???

Thank you for the time you’ve spend reading and helping me out :slightly_smiling_face:

upping my message in case of others may be interested ! :wave: