Those notes are created with Obsidian and I recommend using it to review them. However you can try to open them as they're and read what they contain.
Those are notes that could potentially help with engagin in activities such as Red Teaming, Pentesting or Bug Bounting. I wouldn't call it ultimate guideline for doing so, but there is some knowledge that otherwise could be gained from internet or books. It isn't something you wouldn't find online. However I try to combine every piece of information I gain in this not-so comprehensive guide. I will try to update this knowledge vault everytime I encounter something new or gain more knowledge through courses or books.