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The idiom is "Do ____ from the comfort of your ___".

It's possible that your interpretation of what the phrase is trying to say is what's mixing you up.

The sentence is trying to say that people, given the option, would choose to work from home than in an office somewhere.

Your interpretation would imply that people work to make their home more comfortable... which is probably also true but not what the intention is.

So, examples of this phrase are:

Order now from the comfort of your couch!
Earn money from the comfort of your home!
Online learning from the comfort of your own home.
How to enjoy Burning Man from the comfort of your own home.

(note, these are often sales pitches or scams...)

As a note, "in" is definitely an option here as it is commonly used, too... but there is another idiom "work from home" which makes "from" the better option in my opinion.

According to the Oxford Learner's dictionary entry for fond, "fond of doing something" can mean liking to do something that other people find annoying or unpleasant, and doing it often. Using that definition, "very talkative" would be the correct choice.

When we're using "fond" in that sense, we often (but not always) say something like "a little too fond" or "very fond".

Albert is very fond of interrupting me when I speak.

A similar expression is "like to hear oneself talk": [for someone] to enjoy one's own talking more than people enjoy listening to it. That has the sense of talking just for the sake of making noise, or talking a lot but not saying anything interesting.

Don't worry about the parts of the speech you missed — that guy just likes to hear himself talk.

A related expression is "liking (or loving) the sound of one's own voice". These both have the sense of being pompous or arrogant.

Sherry just loves the sound of her own voice — she made a toast at dinner last night and spent 20 minutes talking about herself.