The default services that are enabled at boot on a Linux system will depend on the distribution and version of Linux that you are using.
Generally, a Linux system will enable a number of services at boot, including core system services such as the init system, the network service, and the filesystem service, as well as other services such as the SSH server, the cron daemon, and the log daemon.
To view the default services that are enabled at boot on a Linux system, you can use the systemctl command with the list-unit-files option and the --type=service option to list the service unit files that are enabled on the system:
$ systemctl list-unit-files --type=service
This will print a list of the service unit files that are enabled on the system, along with their status (e.g., enabled, disabled, etc.).
You can also use the systemctl command with the is-enabled option to check the status of a specific service unit file:
$ systemctl is-enabled SERVICE
Replace SERVICE with the name of the service unit file that you want to check. This will print the status of the service unit file (e.g., enabled, disabled, etc.).
These are just a few examples of how to view the default services that are enabled at boot on a Linux system. The specific steps may vary depending on the distribution and version of Linux that you are using. You can refer to the documentation for your distribution for more information on how to manage services on your system.