I might have some of the terms mixed up, these are all the commands I remember:
Print: Used to show text on screen, in code it should be used as - print "Text"
Assigning a value to a variable: Should be shown as Exemple=3 or Exemple$="3" - The $ shows that the variable is text. Without it, the variable can only equal a number. You can print a variable with - print Exemple or print Exemple$
If: Used to confirm if a variable is equal (==), not equal (!=), greater than (>), lesser than (<), equal or greater than (>=), equal or lesser than (<=), then chooses what to do if the variable meets the condition. Using it in code - if Exemple==3 then @3
The @3 is a label: To make a new label go to a new line and write @Exemple_LabelName, or anything else you want to name it.
Everything until a new label name, a GOTO or GOSUB statement, or an End statement (more later) For simplicity I suggest naming it after whatever you want to happen in the label.
Labels are useful with the if statement for when different conditions are meant.
CLS means clear screen, only for text. Use ACLS to clear graphics.
Under that, I showed how to set a variable, then I show an IF command. You can also add a command to go to another label with any other condition with ELSE. Because EXEMPLE equals 5, it goes to @HI and prints EXEMPLE2$, "HELLO". Then it goes to @NEXT with the GOTO co, prints "WORKING", and with nothing in between, it goes to @END.
I had some time to learn with a different program that had a tutorial. If you type in the commands I gave you and click the help option in SmileBASIC, it will have a more complete explanation for some of the commands I gave you, as well as more examples.
It took me a while. But, I suggest using the help tool after you type a command to know what it does and a few other things. You can also post questions to get it answered. (Like I got help from someone involving collision data)
It is hard man, i understand your frustration. I understand the basics but it gets very complicated. Best way to learn is start coding simple programs, use the manual and you can easily code the area of a circle w/variables.