Read & Publish agreements only cover journal articles, not books or book chapters. Unfortunately, there is currently no internal funding at the Graduate Institute.
If the research that is the source of this book/chapter has been funded by a funder, they will usually pay for the Open Access publication.
If you are unable to publish a book chapter open access, you can self-archive the accepted manuscript in the same way as journal articles.
You can usually find the conditions of each publisher (including embargo periods) on their website. Alternatively, you can also contact me for guidance.