Bypass ios 14.3 on windows packages & all tool needed are below provided for procedure watch video, if any question as in comments 
lets get start first download the ubuntu iso and make bootable usb from it then boot you system with this ubuntu dont yet install it just click try ubuntu it will load its GUI for first use after that download cheackrain from the browser firefox in ubuntu as i do in video or copy it from you download ifrp package to the desktop of ubuntu
now right click on desktop & click open terminal
when windows of terminal open type two commands first
chmod 777 checkra1n
after successful run type second command to open checkra1n note in checkrain dont write i its 1 checkra1n now run second command
sudo ./checkra1n
wait till new windows open when it open plug your phone after plug it will show phone is connect if phone is in normal mode it will reboot it in recovery after that recovery it will guide you to reboot into dfu just follow it will it say done like show in video after successful jail break go back to your windows
now run from download ifrp run it as admin now chose threaded or unthreaded unlock by button wait it will black and run code several time till it show menu dont touch anything at all when menu appear just enjoy
Download Link ubuntu iso https://free4alldevices.blogspot.com/2019/10/linux-ubuntu-iso.html Rufus https://free4alldevices.blogspot.com/2020/04/rufus-new.html Ifrp https://free4alldevices.blogspot.com/2020/12/iphone-icloud-142-os.html for more like sub comments and stay connected for more updates God may bless us all Ameen
Download
Ifrp checkra1n
password is free4alldevcies
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