If for some reason you've to use the spyware OS Windows10 then why don't you at least use these great libre programs and games? Think of it as a first step towards more privacy on your desktop.

All mentioned software is open source and cross platform (works natively on Linux)

Media player

VLC

  • Most feature rich video player

Clementine (music player)

  • If you want an older style dense UI

Elisa (music player)

  • if you want a more modern UI

PDF reader

Okular

  • supports many formats, including PDF, EPub, DjVU and MD for documents; CBR and CBZ for comics; and many more.
  • Supports annontations, text selection and more.
  • Download from here

Office software

LibreOffice

  • Best free office suite and a great alternative to Microsoft Office

  • Compatible with a wide range of formats such as Microsoft

  • Supports extensions

Browser

Firefox

  • Check this post for why you should use Firefox and ditch any other browser.

Torrent

qBittorrent

  • Polished User Interface, Well-integrated and extensible Search Engine, RSS support, Sequential downloading (to watch media while downloading)

Deluge

Screenshot

Flameshot

  • Very light, easy to use with a customizable appearance, screenshot editing and uploading to Imgur

Imagie viewer

Nomacs

  • Beautiful interface, supports most image formats, image editing and more

Archive Utility

PeaZip

Text editor

Kate

Password manager

KeepassXC

File explorer

Dolphin

  • lightweight and feature rich, multiple tabs and split view features allow navigating multiple folders at the same time, access to cloud services and more

Artistic/Creator software

Blender

  • 3D creation suite and a whole lot more

Krita

  • Professional painting program with great features

GIMP

  • Photoshop alternative
  • Those used to Photoshop's interface should check PhotoGIMP out. It's a patch that makes GIMP look like Photoshop

Ardour

  • digital audio workstation

KDENLive (video editor)

  • use it for basic video editing or professional work, supports almost all audio and video formats

  • Titler, many effects and transitions and a lot more

  • Configurable themable interface and shortcuts that can also be configured

Audacity

  • Great audio editor and recorder

Inkscape

  • A vector graphics editor for drawing and making illustrations

CAD software

OpenSCAD

FreeCAD

Gaming

Minetest

  • Minecraft alternative

Dolphin emulator

0AD

  • Reak time strategy game of ancient warfare, got great graphics

Xonotic

  • first-person shooter with multiplayer support

Veloren

  • Multiplayer RPG

Game engines

Doom

  • open source engines, not free assets unless you use freedoom

OpenRA

OpenMW

RetroArch

Godot

More linux software on windows

If you want to go further and try out some of the software that would come with many linux distributions out of the box with a desktop environment called KDE Plasma.

KDE Plasma is a desktop environment, which is basically the foundation of your computer's desktop, it controls taskbars and start menus, docks and panels, titlebars and close buttons, settings and configuations. The KDE desktop uses a toolkit that's cross compatible with windows, so it's possible for the devs to port their software over to windows (like krita, Okular and kdenlive).

While porting is still a somewhat large task thanks to how different windows is compared to linux, there's a pretty good library of windows binaries of KDE programs here. Since these programs are made for linux it's important to note that they won't be as good as they would be on linux, they probably won't be as stable either because they just don't have the same kind of freedom as they do on linux, but it's good for understanding some of the core software.

This post only presents a curated sample of available cross platform software so feel free to ask for more alternatives

Check this post for open source apps on Android

If you ever have a libre related question, come ask in !libre