high-resolution images and transcriptions of nearly 1,200 sheets of the original Leonardo Da Vinci manuscript collection, the Leonardotheka 2.0, ( but it's a very slow website to load)

https://teche.museogalileo.it/leonardo/home/index_en.html

https://news.artnet.com/art-world/leonardotheka-da-vinci-codex-2779022