Yes this is possible.

On the Free package, the only way is via "Forgot Password" option which is on the main login page.
This will then auto generate a new random password.

On either the Premium or the Premium Plus+ package, you can set your password to be one of your own choice:

Once logged in, on the right hand side in the ‘User Menu’ go to ‘Change Password’.

However we do recommend that a strong password is used to maintain security. e.g. no dictionary words, mixed upper and lower case character, use numbers, use special characters, use at least 10 characters.