It's a start!
For buttons use the command BUTTON(). As in:
IF BUTTON() AND {button code} THEN {do something}
The button code is which button you want. Here is the list of codes:
1- up, 2- down, 4- left
8- right, 16- a button, 32- b button, 64- x button, 128- y button, 256- l trigger, 512- r trigger
Here's an example:
IF BUTTON() AND 16 THEN GOTO @START
0そうだね プレイ済み