This is XeTeX, Version 3.141592653-2.6-0.999998 (TeX Live 2026) (INITEX)  14 MAY 2026 14:46
 restricted \write18 enabled.
 %&-line parsing enabled.
**\nopagenumbers \font\test="Latin Modern Roman" \test hello \bye
! Font \test="Latin Modern Roman" not loadable: Metric (TFM) file or installed 
font not found.
<to be read again> 
                   \test 
<*> ...mbers \font\test="Latin Modern Roman" \test
                                                   hello \bye
I wasn't able to read the size data for this font,
so I will ignore the font specification.
[Wizards can fix TFM files using TFtoPL/PLtoTF.]
You might try inserting a different font spec;
e.g., type `I\font<same font id>=<substitute font name>'.

! Undefined control sequence.
<*> ...\test="Latin Modern Roman" \test hello \bye
                                                  
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.

! Emergency stop.
<*> ...\test="Latin Modern Roman" \test hello \bye
                                                  
*** (job aborted, no legal \end found)

No pages of output.