Thumbs up! We do enjoy helping people who want to learn.
However, your project might not be suitable for a beginner. We’ll need more information to determine if it’s even possible.
First, something you may not have considered: are you aware you can add dictionaries to Apple’s Dictionary app? It comes with a bunch of them and you can download more online. It may be that the particular dictionary you want has a compatible version.
If GoldenDict it’s your only option, it will either need to support AppleScript (best option)—which from a cursory glance it looks to not be the case (but you should ask the developer)—or store dictionaries in an accessible format you can parse with some programming.