The Buddha summarized his teachings very succinctly in the 22nd sutta of the Majjhima Nikaya: “One thing and one thing only do I teach, suffering and how to end suffering.” 
This is expanded upon by the Four Noble Truths, which—in essence—state: 1) dissatisfaction exists, 2) it exists because we cling, 3) therefore we should stop clinging, 4) following the Eightfold Path can mitigate our clinging and dissatisfaction. .
And the Eightfold Path , in short, is:
- Right View: accept reality
- Right Intention: strive toward frugality and goodwill
- Right Speech: avoid deceptive, harmful, and idle speech
- Right Action: avoid killing, stealing, etc
- Right Livelihood: pursue careers that don’t harm others
- Right Effort: act with diligence
- Right Mindfulness: value the moment
- Right Concentration: meditate
And that’s pretty much it.
 (SN 56.11)
 Eightfold Path for the Householder