If the icon has just disappeared from it's normal location (start Menu or Desktop Etc), you need to open the file explorer and locate the application .EXE file, It will normally be in either program files or program files (x86) but easiest to search for coreldraw.exe (going from memory so you may need to try to find it manually, Check the folders above for a corel folder and then look for a suitable exe file.
Once you have located the file right click the file and drag the file to the desktop - when you release the mouse button the will be an option shown to Copy, Move, Or Create Shortcut, choose the last option and clicking the shortcut will start the EXE file for you