Let’s see- do you have a comment page up? Should be one from the initial default install. Let’s see what that looks like. They may already be enabled.
And where all do you need to enable and tweak? For each member group- in ‘Admin- Members and Groups’ if you edit the group, you’ll see ‘Comment Posting Privileges’- so you can determine per member group whether they can comment- assuming comments are enabled.
Then- you can enable comments on a per weblog basis- in ‘Admin- Weblog Admin- Weblog Management’- edit each weblog and under ‘Comment Posting Preferences’ you can specify the requirements for posting a comment.
By default, they’ll be enabled. (And you can also specify it on a per entry basis- in ‘Options’, so you may decide not to allow comments- or to set a comment expiration date- for an entry, even if commenting is allowed in the weblog.)
But it’s likely working now- do you have a comment page up? - see the docs on the various EE tags that are used to display comments and the comment form.
Make sense?