I have tried to steer a middle path between too much detail and not enough detail here. If you find you would like more detail, or just get fascinated by the whole area of measuring carbon footprint, then why not buy Mike Berners-Lee’s bible on the subject. Make sure you get the latest revised edition.
https://www.waterstones.com/book/how-bad-are-bananas/mike-berners-lee/9781788163811