Need help with industries.

[jt23]

Hello, so I have played this game on and off for several years, but I am far from an expert. Anyways, I am having a few issues with industries and production. So at the moment I am playing Open Loco, and I have a train that carries chemicals to a factory which produces goods. From there, I have trucks that carry the goods to the adjacent large city and stop at a few depots throughout the city. The thing is the output seems to be very limited from both the chemical plant and the factory, and I am wondering how to increase this. Also, most of the time when I click on the factory, it says it requires chemicals to produce goods, even though I have two or 3 trains that run often enough that there is usually not much waiting time for a train to arrive at a station. I also made the stations max length and made the trains match the length of the platform.

So what can I do to increase production so that the factory makes more goods and shows it is producing them, and am I correct that I am supposed to deliver the goods to the city? Do I need to concentrate the depots near the office buildings?

Thanks