Hey there,

Currently, there is no documentation for it.

1) If I am not a friend of yours, but I do follow you, what can I see when you post, on your profile, etc.?

The followers can only see those updates/posts if they are allowed to view them(satisfy privacy requirements).

Also, you can go to the Following filter to see what is their(those that you follow only) activities as shown in the screenshot.

2) If I do not want someone to be a friend of mine, can I keep them from following me?

Yes you can, you can let them follow you only instead of adding you as a friend.

3) What privacy setting would someone select to avoid allowing someone to Follow them or see something they're doing?

For 'see something they're doing', it depends on what setting have you set for your privacy.

For 'What privacy setting would someone select to avoid allowing someone to Follow them', if you wish to disable this 'Follow' feature, you can disable 'Enable Followers' which is at Backend > EasySocial > Settings > General > General.