This probably was asked countless times already, but given the amount of possible combinations of all the hardware and software, this is probably not surprising.

So, I do have some experience with linux. I ssh into my ubuntu server a lot, I do many bash/terminal tricks, so can't really call myself a newbie in Linux. However, for gaming I would use Windows for as long as I remember myself. With the release of KDE Plasma 6 and Vulkan support getting better, I was thinking about giving it a go, but I'm stuck.

When launching a game that natively supports linux (Dota 2) from Steam, pretty much nothing happens. I see in terminal that there are some errors, but archwiki states that this is normal:

Wrong ELF class

If you see this message in Steam's console output

ERROR: ld.so: object '~/.local/share/Steam/ubuntu12_32/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.

you can safely ignore it. It is not really any error: Steam includes both 64- and 32-bit versions of some libraries and only one version will load successfully. This "error" is displayed even when Steam (and the in-game overlay) is working perfectly.

Other than that I see no errors or anything.

I'm running Arch linux with KDE Plasma 6.0.1, with default Wayland session. My laptop is an Acer Nitro 5 with NVIDIA GPU and I guess also Intel integrated video card. Here are the details:

Operating System: Arch Linux 
KDE Plasma Version: 6.0.1
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.2
Kernel Version: 6.7.9-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 16 × 12th Gen Intel® Core™ i5-12500H
Memory: 15.3 GiB of RAM
Graphics Processor: Mesa Intel® Graphics
Manufacturer: Acer
Product Name: Nitro AN515-58
System Version: V1.13

I have no idea honestly about which driver I have installed, but I did install nvidia package. I'm not sure if it's being used. I also don't know anything about Mesa. Also, this is from my Info Center:

KWin Support Information:
The following information should be used when requesting support on e.g. https://discuss.kde.org.
It provides information about the currently running instance, which options are used,
what OpenGL driver and which effects are running.
Please post the information provided underneath this introductory text to a paste bin service
like https://paste.kde.org instead of pasting into support threads.

==========================

Version
=======
KWin version: 6.0.1
Qt Version: 6.6.2
Qt compile version: 6.6.2
XCB compile version: 1.16.1

Operation Mode: Xwayland

Build Options
=============
KWIN_BUILD_DECORATIONS: yes
KWIN_BUILD_TABBOX: yes
KWIN_BUILD_ACTIVITIES: yes
HAVE_X11_XCB: yes
HAVE_GLX: yes

X11
===
Vendor: The X.Org Foundation
Vendor Release: 12302004
Protocol Version/Revision: 11/0
SHAPE: yes; Version: 0x11
RANDR: yes; Version: 0x14
DAMAGE: yes; Version: 0x11
Composite: yes; Version: 0x4
RENDER: yes; Version: 0xb
XFIXES: yes; Version: 0x50
SYNC: yes; Version: 0x31
GLX: yes; Version: 0x0

Decoration
==========
Plugin: org.kde.breeze
Theme: 
Plugin recommends border size: None
onAllDesktopsAvailable: true
alphaChannelSupported: true
closeOnDoubleClickOnMenu: false
decorationButtonsLeft: 0, 9, 2, 6
decorationButtonsRight: 1, 3, 4, 5
borderSize: 0
gridUnit: 10
font: Noto Sans,10,-1,0,400,0,0,0,0,0,0,0,0,0,0,1
smallSpacing: 2
largeSpacing: 10

Output backend
==============
Name: DRM
Atomic Mode Setting on GPU 0: true

I don't even know what is Xwayland and why I have it installed, probably some dependency of KDE.

At this point I'm not even sure what I'm using (is it pure wayland, or x11, or some hybrid of using both), if I have correct GPU drivers (do I have correct drivers for just one of the two video cards, for both, or none at all), if my NVIDIA GPU is even working, if it's being used to run a game or not, and if I have all necessary packages to run Vulkan.

At this point, how do I troubleshoot all of this mess?