Don’t use random links from the interweb
Use Manjaro Linux Web Download page.
Manjaro Linux has repo package with a script and a simple GUI to download and verify a Manjaro ISO.
sudo pacman -Syu manjaro-iso-downloader
Another option is to use the script from this topic on [root tip] [Utility Script] Using python to download and verify a Manjaro ISO
- GitHub - fhdk/manjaro-get-iso: Download Manjaro ISO and verify signature
- root/manjaro-get-iso: Download Manjaro ISO and verify signature - manjaro-get-iso - nix.dk
The most versatile method to boot the ISO is to use ventoy - also in the Manjaro Repo.
Ventoy is a tool to boot an USB stick (with a selection of ISO files) then select which ISO to load.
sudo pacman -Syu ventoy
The ISO can also be written to a USB stick - ensure you use the a method compatible with dd utility.
Due to the way the ISO is assembled and booted - utilities which unpacks the ISO and writes the content to the USB will not work.