Welcome to Linux and Kubuntu. Please don't give up so easily. Kubuntu is a wonderful operating system which requires a bit more effort than Windows to learn, but the rewards are worth it. And its all free and open source.
As you are new to Linux (and Kubuntu) and to a new PC given to you, may I suggest you start at the beginning by formatting and re-installing Kubuntu or Ubuntu 22.04.1 as a fresh new install. This will give you full control.
Please read or watch a youtube video on the differences between Kubuntu and Ubuntu and then decide which one to install. The only difference is the desktop environment. Ubuntu uses Gnome, and Kubuntu uses KDE Plasma. Some beginners perfer KDE Plasma, and some prefer Gnome. KDE plasma feels more like windows, whilst Gnome feels minimalistic more like a MacOS (in my opinion). KDE Plasma is fully customisable, and Gnome is more minimalistic and less customisable.
The installation process is simple, and there are many youtube videos and online articles showing you each step of the way. A fresh install can also let you set some options like with or without proprietary software/drivers, disk encryption and so on.
Once you install Ubuntu/Kubuntu, you can then learn things step by step.
To install Ubuntu/Kubuntu you will need to download the ISO file, then create a bootable USB drive with that ISO file using something like BlenaEtcher, and then re-boot from that USB. That will bring up the installer.
Best of luck, and welcome to Linux!