Greetings @thoaho86 !
We warmly welcome you to the Unreal Engine community! 
Just so you’re aware, I’ve had to move this topic from the Getting Started forum to the Asset Creation forum. I’ve added the optional tags, “question”, “Mesh”, and “import” for you.
You aren’t wrong in choosing the Getting Started forum, it’s just that our other forum topics are more targeted for the issue that you are having. It is best practice to review the categories to ensure your topic is posted in the most relevant space.
Wishing you the best of luck in solving the asset issues you are having,
Your Friendly Neighborhood Moderator 