I’m a first-time visitor to Seoul—are the subway and taxis easy to use? Which is better?

I’m a first-time visitor to Seoul— is the subway easy to use? 🚇💭 Or is getting around by taxi more convenient? 🚕 I’ve heard the subway is convenient because there are so many lines, but I’m a little worried about transfers…🥺 I’d love to hear honest opinions from people who’ve actually traveled there! If you have any recommended ways to get around, please let me know✨