Ssh options for users in hestia cp

hi, i’ve looked for a proper article, in here and in the documentation, and I couldn’t find much about the SSH options for a user … bash, dash, sh …
How do these things work … and what are they made for ?
(my need is to give ssh access to a user in hestia, in order to install dokos/ERPnext in a subdomain through shell/ssh) thanks

Use bash