TIL beginner Javascript

I used a video on Youtube by FreeCodeCamp to teach myself the very basics of Javascript today.
I'd start with saying you must sign up for a platform site that will allow you to run Javascript- since I'm going to University this summer I believe they will be telling me which one to use, so I'm going to update which I end up using later. Today is just in theory and in preparation to go to school.
BASIC RULES:
All lines end with a semi-colon // not required just polite//
Capitals matter- must be an exact copy of original spelling with capital placements to be processed.
The intro to Javascript is how to leave comments.

1. //Leave a comment that's one line//
2. /* Leave a Comment that is mulitple lines*/ AND the pieces you need to begin coding like: 1.var variable= "number or script, can change"; variable= 9;
3. let allowsNumberScript = "only applicable to a scope of code";
4. const variable = remain constant; In addition var can be declared or assigned: //= sign is the assignment operator// assigned: var a; declared: var b=2; assigned:a=7; assigned: b=a; a=7; console.log(a) console >7 //placement of console log matters in Javascript// var a; var b=2; console.log(a) b=a; a=7; console >null >7