Questions about Arrays

How do I define a scene array?
Do I just append a variable to array and it will automatically create it and initalize it?
How do I access first or any member of an array? (There is no array expressions offered in any of “Change scene variable” type of functions)

Did you try reading the wiki? Variables [GDevelop wiki]

I did and I know what an array is. It still does not explain how do I properly use it within a function.
Lets say that I append variable “var” to an array “sequence”.
Now for example I want to see if the first number is greater than 5.

In the “Compare scene variable” function there are only expressions related to scene variables and global variables, no arrays whatsoever.
Maybe scene arrays are treated same as regular scene variable?
If so, how do I access certain member of such array?

Variable(sequence.0) or Variable(sequence[0])…?

Well yes, the wiki page says that this is the syntax for all collection types.

Now I see, thank you very much.