If you’ve never installed Linux before, I would start with something user-friendly, like Kubuntu or Bazzite. Both come with KDE as their main Desktop Environment (“DE”), so you could do what OP did looks-wise.
If you’re a technical user, and don’t hate having to sometimes do things manually, try Garuda Linux - it’s Arch-based, but catered very towards Linux newbies and does a lot of hand-holding. I use it and I enjoy it very much.
To specifically do what OP did with his DE - KDE comes with the concept of Panels and Widgets. The top bar you see in the screenshot is a Panel. On it, there are (from right to left) the System Tray widget, a Spacer widget, a Digital Clock widget with customised display format (something you can do in the settings of the widget), another Spacer, an Icons-Only Task Manager widget (displays active applications and lets you pin applications - like the Taskbar in Windows or Dock in macOS), and finally the Application Launcher widget (the Start menu equivalent). Everything is pretty heavily customised (presumably with Panel Colorizer? Not sure), so that - out of the box - even with this exact setup copied, yours would look slightly different.
If you’ve never installed Linux before, I would start with something user-friendly, like Kubuntu or Bazzite. Both come with KDE as their main Desktop Environment (“DE”), so you could do what OP did looks-wise.
If you’re a technical user, and don’t hate having to sometimes do things manually, try Garuda Linux - it’s Arch-based, but catered very towards Linux newbies and does a lot of hand-holding. I use it and I enjoy it very much.
To specifically do what OP did with his DE - KDE comes with the concept of Panels and Widgets. The top bar you see in the screenshot is a Panel. On it, there are (from right to left) the System Tray widget, a Spacer widget, a Digital Clock widget with customised display format (something you can do in the settings of the widget), another Spacer, an Icons-Only Task Manager widget (displays active applications and lets you pin applications - like the Taskbar in Windows or Dock in macOS), and finally the Application Launcher widget (the Start menu equivalent). Everything is pretty heavily customised (presumably with Panel Colorizer? Not sure), so that - out of the box - even with this exact setup copied, yours would look slightly different.