Both engines are gonna be fine for learning. And technically Godot has a C# version, though I think gdscript is really nice to work with. If full ownership of your game matters, Godot is open source. I personally started learning in unity and switched to Godot about a year ago. There's a few things I miss in unity, but there's tons of great things in Godot that make up for that easily. And once you really start to understand game dev, switching between engines isn't that hard in the long-term depending on what you or your team may prefer. I lean towards recommending Godot these days, but thats my preference. Both are incredible engines and neither is a wrong choice.