Unix basic help

What command would I use to list the first lines of all
text files within my Unix directory or within any directory
inside there? I was using "find" , "head" and "-exec" commands like this:

find ~/Unix -name "*.txt" -exec head {} \;

But its not perfectly working, please help me. thanks

This might work?

for file in ~/Unix/*.txt; do
   head $file
done

Try...

find ~/Unix -type f -name '*.txt' -print | xargs head