Which is easier? I used to write in first person when I was younger since I thought that would be easier, but after working on 2 stories, one in third person and another in first person, I'm finding third person is better. With third person, at least for me, I can do a better job at world building, while in first person it's easy to forget including details that the main character won't know about, that I as the author, know.
Which one do you guys prefer more?
Third person writing is what is taught primarily in schools. It is also the format of academic writing for most subjects and in most instances. Therefore, third person writing styles tend to be more accessible for the public. However, just because they are accessible does not mean that they are more simple to write.
Consider the following: narrator, voice, grammar, speech.
With first person writing and first person literature, both the narrator and the voice of the author are decided. Preclusion of narrator and voice makes writing in the first person far more familiar when the author's first person is of similar voice to the author; this is why some webnovels and light novels have such an easy time of new content. Speech, being what it is, covers great lengths of narrative content or plot with incredible brevity, e.g. "What's up?" "Chillin'." Third person narrative, on the other hand, is more verbose with the tradeoff of being more versatile, e.g. a first person narrative must be extremely creative when expounding on minute details of a new world: most first person isekai novels avoid extensive worldbuilding in the first person by using classroom settings or suspending the first person narrative for an interlude.
With respect to grammar, first person tends to be more difficult because it necessitates both a concrete understanding of grammar, formatting, script communication or speaking skills, and is even enhanced by a great number of other bizarre things such as dialectic, slang, multilingualism, etcetera. Failure in the first person is also far more damning than failure in the third person, as the reader will not only disenjoy your literature but will also have no idea what it's about. First person writing also allows for greater creativity in formatting, as the entirety of its literature is subject to the linguistic whims of the first person. Even outside of speech bubbles, a first person narrative could read like "YOOOOOOO DAWG x1133333xD" if the author wanted it to, and it wouldn't necessarily break with the structure of the literature.
Speech, well, that's always difficult. Try to imagine a conversation with your best friend. Are you finished? Then call your best friend and do your best to stick to the script. Can't do it? Neither can I. :^)