By default, the ansible-doc command will use module as the type, thus the -t or --type option followed by become must be used to display documentation on become.

The -l or --list option can be used to list the become documentation, which lists the various become methods (e.g. become_method: sudo).

ansible-doc --type become --list

doas       Do As user
dzdo       Centrify's Direct Authorize
enable     Switch to elevated permissions on a network device
ksu        Kerberos substitute user
machinectl Systemd's machinectl privilege escalation
pbrun      PowerBroker run
pfexec     profile based execution
pmrun      Privilege Manager run
runas      Run As user
sesu       CA Privileged Access Manager
su         Substitute User
sudo       Substitute User DO

Let's say you want to learn about "sudo". The -s or --snippet option can be used.

ansible-doc --type become --snippet sudo

You can also display information about the shell module, like this. Refer to Ansible - become parameter for more information on the become parameter

ansible-doc --type module --snippet become