How on earth did they fail so badly, is it me or are Zelenskyy and Netanyahu are similar in sending waves upon waves of newbees into a war zone with little training
They are conscripts/reservists. Israeli citizens (with some exceptions) are obligated to serve a minimum of 32-36 months in the military, after which they can be called up at any time until age 40.
Don't expect these guys to have any major strategic and tactical knowledge apart from basics, nor the personal drive for combat.
I have my doubts about their 126,000 active personnel. The number is probably closer to 50-60K retinue/standing army.
Edit:
Also, morale is not on their side in this war. They can see the entire world viewing them as criminals. Earlier this year, there was a massive internal disorder within the military with reservists refusing to attend service due to political developments. And then.. they were suddenly thrown into war at gunpoint.