Make sure it's opening the correct desktop. I was wondering what happened to my desktop once, and I found that it had gotten set to a different virtual desktop and that I should push...
Windows Key plus P and when I did I saw that there was the option to switch back to my normal desktop and everything went back to normal.
Not sure if that is your problem, or that it works that way in Windows 11, so have a look at this.
The virtual desktops feature gets a makeover in Windows 11. Here's how to organize and customize them in Microsoft's next-gen OS.
You can also try opening the start screen "left click start button" and type in what you are looking for when it shows you the app, right click on it and select pin to taskbar. You can probably put them back, one at a time.