Recommend to me some good RPG games that are available on PC.
Here are some highly rated RPG PC games:

- The Witcher 3: Wild Hunt - Widely considered one of the best RPGs of all time. Open world fantasy game set in a gritty world, allowing you to play as a monster hunter.
- Skyrim - Another hugely popular open world fantasy RPG set in the Elder Scrolls universe. You can explore the land of Skyrim and battle dragons as a warrior, mage or thief.
- Fallout 4 - Post-apocalyptic open world RPG set in a retro-futuristic wasteland. You can craft weapons and armor, build settlements and make key choices in the story.
- Divinity: Original Sin 2 - Turn-based fantasy RPG with a major focus on player choice and consequences. You control a party of characters with different abilities and can interact with the world in complex ways.
- Pillars of Eternity - Classic style RPG with a strong focus on story and characters. It has a tactical real-time combat system and allows you to recruit companions to join your quest.
- Mass Effect 2 - Sci-fi RPG shooter set in a futuristic universe. You lead a team on a mission to stop an alien threat, making key decisions and developing relationships along the way.

These are some of the most popular and highly rated RPGs for PC that provide deep stories and character progression as well as exploration of open or large worlds. Let me know if you would like any additional recommendations.
I'm curious why you recommended Divinity: Original Sin 2 (sequel), but not the first game. I haven't played either of them, would it be ok to start with DOS2 from the plot standpoint?
Divinity: Original Sin 2 takes place centuries after the first game, and can be played standalone. In fact, many have only ever played the sequel- one of the main reasons I recommended Divinity: Original Sin 2 over the original is because it's more popular than the original. This is reflected in the more positive reviews compared to the original, and its inclusion on several best of all time lists.