In the article for Agile Software Development, there are six thousand, eight hundred words and over 100 references.
The Agile Mainfesto is 73 words. Gobs and gobs of software has been written to "do agile". Every software shop I've encountered in the last decade has told me they use an agile software development process. Being an "Agile coach" is an entire career.
But the whole manifesto is just not all that.
The entire body reads as follows:
We are uncovering better ways of developing software by doing it and helping others do it. Through this work we have come to value:
Individuals and interactions over processes and tools
Working software over comprehensive documentation
Customer collaboration over contract negotiation
Responding to change over following a plan
That is, while there is value in the items on the right, we value the items on the left more.
That's it. Focus on relationships with people, and actually solving problems.
Moreover, the Manifesto ends with a sentence to weasel out of any actual firm stance. The other stuff is also valuable.
You'll never do Agile right, because there's no way to prove that you're doing it right. Don't make user stories and have retrospective meetings just because it says to do so in some book or by some coach.
Do what works for whatever your situation. Just make sure your values and priorities are in order. That's the whole manifesto.