1 . ant -help
This command executed in command prompt gives helpful information about what are all parameters present to execute the ant command.
2. Ant official Documentation : https://ant.apache.org/manual/index.html
Above link provides detailed developers documentation about all capabilities of ant build. It can give detailed documentation about syntax, procedures, what are all in built tasks available, how to create customized tasks, how to configure Ant with various development IDEs etc.