Beginner questions about film scoring

Hi, everyone, I'm new to this forum. I have some basic questions about film scoring.

I play the piano, and I can compose musical themes on there. I have trouble converting it to orchestra, however. I have even more trouble creating the realistic movie sound I'm looking for.

The software I have is Finale 2008 and Garritan Personal Orchestra 3. I know a lot can be done with these, but I simply don't know how to use them to their full potential.

I want to make something in the general style of Anne of Green Gables, but I'll need some help. Please bear with my newbie questions. Since regarding film scoring, I'm a relative beginner, I'll need some basic questions answered.

As the first step, how big is the orchestra in the above soundtrack? Is it possible to make this kind of score with Finale and GPO?

Step 1: Learn how to compose for orchestra

Step 2: Learn how to use VSTs

Step 3: Learn sequencing.

Step 4: Mix the above and bake for 45 minutes.

Can you recommend a low-cost or free way to learn to compose for orchestra?

And, it does take a while. Don't expect results in a month.