Hello
As long as you are a college student, you can apply for Google Summer of Code program, i.e., It doesn't matter if you are in the first year of undergraduate studies or a PhD student.
Now, going by the general logic here, you in all probability would be acquainted with basic usage of few programming languages and have solved assignments or wrote several small programs in them. It's certainly great but nothing to worry about if you haven't.
Thanks
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