There are plenty of instructional guides on YouTube on how to bind your key fob to the immobiliser As you didn't give any details of the age or version of your Galaxy, I'll avoid giving potentially incorrect info here.
I will, however, suggest that the issue you have could be caused by the fuel cut-off switch being activated. It's a simple thing to rule out before anything else. Also dependant on age, so you will need to google the location for your particular model, but will most likely be in the passenger footwell or under passenger seat. It's a small unit with a pop out button that needs to be pressed in to reset, allowing fuel to be pumped to engine again.