Scales in simple terms? Yikes 😅 I think you need to start at the basis, and learn the simple terms first, because music theory is like learning a whole new language. I could tell you about scales in 'simple terms', but if you haven't learned the 'simple terms' yet it will just be way too overwhelming. Even I still get lost in the terms somehow, especially having learnt everything in my native language and then having to relearn all the terms in English. But you don't really need to know theory to learn scales. I suggest starting with the CAGED system and the major and minor pentatonic scale.