The LibreOffice program has been installed on my computer but no icon on my taskbar or on the computer screen.
Which OS is being used?
If you use MS-Windows OS then browse to the directory or folder in which you installed LibreOffice look for the files with .exe extensions right-click on the writer.exe file select copy shortcut or just copy. Then on your desktop right-click on past shortcut. Then you can drag and drop the icon where you like it.
Or in ubuntu, run libreoffice, or one of its components, and when its icon appears in the launcher, righ click on it and select ‘Add to Favourites’.