The issue of a blinking Q in a folder is telling you the drive you are using either doesn’t have the needed system files or the drive you had in the system was removed and the new one is not known to the hardware.
If you boot up and press the Option key you should be greeted with a menu of drives which are blessed with the OS installed. Using the arrow keys select it and let the system startup. Once started go into your Startup control panel and select this drive. If you don’t see a blessed drive then the drive has failed, not connected or is not running the needed version of macOS.
Reference: [https://support.apple.com/en-us/102603|Mac startup key combinations]
You also talk about odd coloring of the icons, implies the CPU (graphics engine part) has failed. Unlike the 15” model the 13” only uses the Intel Iris graphics engine which is part of the CPU logic. Remove the heat sink and inspect the silicon chip for cracks or damage. Often I find the system overheated and the chip failed.