honestly i think all the engines are capable of amazing stuff, i gravitated towards UE4 because of the visual coding but i know there's plugins that add that to unity. both also have great communities that have thousands of tutorials on everything you can think of
i think the best thing to do would be to pick one and start making stuff - i've been devving on and off since 2017 and i still feel like there's so much more to learn. https://imgur.com/a/gVVSDVi here's some more examples of what UE4 can do in the hands of a total noob if you wanna check it out also
my best tip would be to try and plan out games from start to finish as best as you can before starting, the biggest project killer for me has been not knowing what to do next, or burning out on fixing an issue i hadn't thought about (how multiplayer networking works, save systems, etc.)