I suggest you start by reading through the official e-manual. You can find it here...
http://smilebasic.com/en/e-manual/10.php
After reading it, I suggest just messing around with code, mastering every command through experimentation! If you need help with anything, you can ask away!
There are a lot of commands that are used to manipulate sprites. All of them start with SP, and probably the most basic is SPSET.
This command creates a sprite by giving it a management number and a definition number. The management number serves as the sprite's unique ID, and you use this ID with most other SP commands.
The definition number is basically the sprite itself. You can check all default definition numbers in the Smile Tool by pressing the SPDEF button. The syntax for SPSET is the following...
SPDEF [Management #],[Definition #]
After running this, you should see the sprite in the upper left corner of the screen.
You can change where the sprite is located with SPOFS. It uses the following syntax...
SPOFS [Management #],[X Coordinate],[Y coordinate]
There are a bunch of other instructions that deal with sprites, (most will start with SP, as I've mentioned before) but I'll leave you to explore them on your own. Feel free to ask about anything, still!
Here's an example of placing a sprite of a piece of meat (definition number 16) near the center of the screen:
SPSET 0,16 'WE LEAVE 0 AS THE MANAGEMENT NUMBER
SPOFS 0,200,120 'WE SPECIFY THE SPRITE'S MANAGEMENT NUMBER, AND THE COORDINATE (200,120), WHICH IS NEAR THE CENTER OF THE SCREEN
If you want to have multiple sprites, just use the SPDEF command various times with different management #s.