It happens to me in training or when meeting UX designers, sometimes even in mock interviews, to see terms get lost and mixed up. Here is an attempt to put things in order.

Design Thinking, UX design, Design Sprint, Lean UX, Double Diamond, Lean Startup, Scrum

 
If one of the subjects escapes you, you could find your happiness there:

• Article on the Design Thinking.
• Definition videoUX Design.
• The guide to scrum.
• Article on the Double Diamond.
• The book : Lean Startup.
• The toolbox for a DesignSprint.
• The book : Lean-UX.

Have a good day !
@AnnePedroFr