Ubuntu, Debian or Mint are currently having biggest app repository (meaning most applications ready to install and that's the key if you are new or lazy enough to not want to recompile everything and get the system quite fast way.
Also: there is Qubes OS using virtualization as layer of possible protection.
But if you are completely new to it: use Mint - burn liveDVD and start from it
https://linuxmint.com/download.php
On dvd you will have only most basic apps however.
https://distrowatch.com/
There are doubts about systemd in Linux (distrust about possible NSA involvement or distrust for RedHat company being now branch of IBM) so if not Debian you can use Devuan. If you not fear it use Debian: netinstall image (requiring writting it into cd or pendrive - better try with cd if you are new to it - and internet connection) https://cdimage.debian.org/debian-cd/current/amd64/iso-cd/debian-10.8.0-amd64-netinst.iso or "testing" (not so unstable - but it may not be almost rock-stable like previous one "stable") version having newest versions of software: https://cdimage.debian.org/cdimage/weekly-builds/amd64/iso-cd/debian-testing-amd64-netinst.iso
Ubuntu, Debian or Mint are currently having biggest app repository (meaning most applications ready to install and that's the key if you are new or lazy enough to not want to recompile everything and get the system quite fast way.
Also: there is Qubes OS using virtualization as layer of possible protection.
But if you are completely new to it: use Mint - burn liveDVD and start from it https://linuxmint.com/download.php On dvd you will have only most basic apps however.