I had a problem that my laptop ran out of battery when updating and I had an error: you need to load kernel first
so I burned manjaro to a USB stick and booted from it but when I try to update all the packages get downloaded but when upgrading everything freezes including mouse,keyboard and even the time in the laptop I tried updating from both the terminal and the package manager
If you have enough disk space you could make a fresh install just on top of your existing systems and just keep everything except as your ESP as it is. Would be an unusual approach but possible. Usually, I would recommend to backup valuable files from your Manjaro install, delete the Manjaro partitions and then to use this space for a re-install.