It's a complicated game, and figuring out everything thats going on is part of the fun.

I would start with a goal. Lets say abolishing slavery. Laws are different for each country. Hawaii and Great Brittain don't have slavery but most countries do start with slavery. In order to pass laws you need to have interest groups that support it, showed here. The landowners are the ones that will want to keep slavery the most. So you can see them as your primary antagonist. The interest groups most against it are the intelligencia and the trade unions.

Now that you know who your political allies and enemies are you start to think about how you can make them less powerful. The more industrialized a nation is the less powerful landowners are going to be, so focusing on building up industry will reduce their power over time. At the start of the game you will be able to suppress or bolster different interest groups, so using your authority for that early is a great idea. You can also try and pass a law that you know will lead to civil war, say abolishing slavery at the start, then you can see which provinces are going to stay loyal or not. Backing off and then militarizing those loyal provinces so you can feel confident in winning a future civil war is a great idea.

Basically the game is about setting goals like, expanding gdp, passing certain laws, raising standard of living, conquering/colonizing territory, and then deciphering the game's systems in order to make that happen. I almost lost this campaign because I decided to centralize my bureaucracy in a single province that ended up not staying loyal during a civil war. Because of this we didn't have the infrastructure to collect taxes during the civil war and I was actually in default before I managed to barely clutch out the war.

If you enjoy the idea of playing a game that allows you to establish socialism, and the depth of the systems at work seems interesting to you, I'd give it a try. It's a neat game. Two countries I'd recommend to start are Japan and Iran. Both start with a lot of different resources so you don't have to conqueror to industrialize effectively. They also both start isolationist so you don't have to worry about the big powers free trading all your important resources away, it was a huge problem when I played sweeden. It was basically this garfield comic but replacing garfield with france.