The output of your command "curl --help" is:

Usage: curl [options...] 
 -d, --data           HTTP POST data
 -f, --fail                 Fail fast with no output on HTTP errors
 -h, --help       Get help for commands
 -i, --include              Include protocol response headers in the output
 -o, --output         Write to file instead of stdout
 -O, --remote-name          Write output to a file named as the remote file
 -s, --silent               Silent mode
 -T, --upload-file    Transfer local FILE to destination
 -u, --user  Server user and password
 -A, --user-agent     Send User-Agent  to server
 -v, --verbose              Make the operation more talkative
 -V, --version              Show version number and quit

This is not the full help, this menu is stripped into categories.
Use "--help category" to get an overview of all categories.
For all options use the manual or "--help all".