my site

Tebtim 

You mean a "Me Experience"?
You kind of have one here: "https://portal.office.com"

If that is not enought then take a look at this article from Microsoft Learn.

https://learn.microsoft.com/en-us/sharepoint/dev/spfx/build-for-teams-me-experience

They are building a "Me Experience" for teams by creating some SPFX Webparts, building a SharePoint Page with the webparts and embedding that page into teams.....
But you can skip the last part, if you don't need the teams integration.

You get all the webparts you need by installing the sp-starter-kit from PnP

https://github.com/pnp/sp-starter-kit

It includes many useful webparts for this usecase like 

Personal Email

https://github.com/pnp/sp-starter-kit/blob/master/documentation/components/wp-personal-email.md

Personal Calendar:

https://github.com/pnp/sp-starter-kit/blob/master/documentation/components/wp-personal-calendar.md

Personal Tasks

https://github.com/pnp/sp-starter-kit/blob/master/documentation/components/wp-personal-tasks.md

Recently used Documents

https://github.com/pnp/sp-starter-kit/blob/master/documentation/components/wp-recently-used-documents.md

Best Regards,
Sven