Hp Laptop - Defective HP Laptop

I had purchased HP Laptop **Q CS****TU vide Invoice dated **/**/**.
Laptop serial number *CG****KLQ, Model No. RTL****DE
Had been facing smaller issues with the machine from very beginning. This laptop was with a one-yearwarranty and an extended warranty for another * years. The laptop is being used by my Daughter ( Class X ) for attending online classes and school assignments. This laptop is her only connect with the school and the outer world apart from the Mobile she has.
On **/**/**** the screen went blank though the machine had power, this was complained to HP Care India vide Case ID ********** dated **/**/****. The engineer who visited after * days diagnosed the problem as screen problem and came back after * days with a new screen. On arrival the engineer realized that the new screen he got as replacement is faulty but surprisingly the old screen by that time started working on its own and the laptop sprung back to life somehow, which your engineer had no clue about. Anyways things were managed for the time being somehow, irrespective of the fact that the diagnosis of the engineer and your technical team had no efforts in it. In addition, while trying to open the laptop your engineer broke the screw holder close to the screen folding position inside the laptop compartment.
On **/**/**** the problem of screen going blank re appeared and was complained vide Case ID **********, the engineer who visited on **/**/** this time diagnosed the problem related to Mother Board and finally on **/**/**the Engineer replaced the Mother Board after struggling for almost * hours could somehow see the screen coming back to life. We witnessed the way he struggled and somehow could bring back the laptop to life. Though far from being satisfied we had to release him after signing the confirmation. You may please refer to my online feedback in response to your feedback mail dated **/**/**
On **/**/** it was observed that a few of the keys on the keyboard are not responding and was complained against the same Case ID **********. The technical help over phone tried to resolve with remote accesses of the laptop but could not do anything. Though she assured to escalate the issue and have the same taken care of asap.
On **/**/**** morning the screen again went blank and was complained vide Case ID **********. Nothing has been done as yet despite assurances that the matter is escalated and has been put on the priority list.
More terrifying than the problem is the process of booking a complaint and online trouble shooting which is so cumbersome and long drawn that at times you feel like giving up.
Lastly my humble submission. Please be informed that any issue with this laptop is extremely disturbing since it is being used by my daughter for her online school and is her only source to attending schools. Any issue with the lap top means she almost misses the school for those many days. This was one reason that I wanted to give her the best despite being out of reach, and I could not think of anything other than HP.
If you may please guide me as to when and where did I go wrong or what wrong did I do that I am being taken for a ride which might even cost her an academic year of school.