Hello Juan
In the case of the lesson, within the group policy, we see this command:
ASA1(config-group-policy)# vpn-tunnel-protocol ssl-client ssl-clientless
This command indicates that the VPN tunnel when used with a client, will indeed be using SSL. The syntax for this command is:
vpn-tunnel-protocol { ikev1 ikev2 l2tp-ipsec ssl-client ssl-clientless }
You can specify multiple protection protocols in the order of preference that you wish them to be used. If no VPN tunnel protection is configured, then IPSec is the default. Note that the only clientless option is the use of SSL.
There are many VPN clients that you can use, many of which are freely available including OpenConnect, Shrew Soft VPN client, and WireGuard to name a few. You can do a search online for one that fits your needs. Windows has a native VPN client that you can use as well. All of these can be configured to work with the ASA.
I hope this has been helpful!
Laz