Some useful free software

7-zip, file Compression tool (ZIP), https://www.7-zip.org/ 

Firefox, internet browser, https://www.mozilla.org/en-US/firefox/new/ 

Sumatra PDF, simple lightweight PDF reader, https://www.sumatrapdfreader.org/free-pdf-reader.html 

LibreOffice, free alternative to MS Office, https://www.libreoffice.org 

VLC media player, https://www.videolan.org/vlc/index.html 

Inkscape, vector based drawing editor, https://inkscape.org/ 

GIMP, image editing software, great alternative to Photoshop, https://www.gimp.org/ 

IrfanView, classic lightweight image viewer, https://www.irfanview.com/ 

Thunderbird, email client, https://www.thunderbird.net 

Notepad++, https://notepad-plus-plus.org/ 

Filezilla, FTP client, https://filezilla-project.org/ 

Winspc, SFTP/FTP client https://winscp.net/eng/index.php 

XP Burner, CD/DVD burning software, https://cdburnerxp.se/en/home 

Wincdemu CD/DVD/BR emulator, https://wincdemu.sysprogs.org 

FreeCAD, Open Source CAD software, https://www.freecadweb.org/ 

LibreCAD, 2D CAD, https://librecad.org/ 

Blender, 3D graphic software, https://www.blender.org/ 

Shotcut, video editing software, https://shotcut.org/ 

Darktable, digital darkroom software for photography, https://www.darktable.org/ 

SageMath, alternative to Mathematica, https://www.sagemath.org/ 

Kyenslab, free alternative to Origin, https://www.kyenslab.com/en/index.html 

Rufus, for creating bootable usb drive, https://rufus.ie/ 

Recuva, for recovering deleted files, https://www.ccleaner.com/recuva 

Paragon, disk cloning software, free community version https://www.paragon-software.com/free/pm-express/#resources 

WinDirStat, for analyzing storage usage on your computer, very useful if you want to find out what files are taking up all the space on the hard drive, https://windirstat.net/ 

Putty, SSH and telenet client, https://putty.org 

KiCad, electronic design CAD, https://kicad-pcb.org 

Veroboard, CAD for stripboard, https://veecad.com 

LT-spice, Free SPICE software, https://www.analog.com/en/design-center/design-tools-and-calculators/ltspice-simulator.html 

QElectroTech, for drawing electrical diagrams, https://qelectrotech.org 

Termite, simple RS-232 terminal, https://www.compuphase.com/software_termite.htm 

Bitdefender, Windows 10/11 defender says to be good enough but if you need third party antivirus here is a suggestion https://www.bitdefender.se/solutions/free.html