You can make some change if you use a carriage return / newline / enter either before or after the entered text.
If text is all one font / size then the tool to use is Ofnuts plugin see: https://www.gimp-forum.net/Thread-ofn-text-along-path
If text is all one font / size then the tool to use is Ofnuts plugin see: https://www.gimp-forum.net/Thread-ofn-text-along-path