Virtual Gallery

Hi guys ~ I’m new here, and also a beginner :D, I’m currently working and learning to build a project, It’s something like virtual gallery. I’m going to put some art inside and planing to publish it on web, is that good for using UE4 ? Do I have to pay for that ? Also I’m struggling on the modeling part, I built some model using blender and wanna put it into UE4 but give me certain error, need some help please, is there any tip or rules while making the model in blender that I want to import it to UE4 ltr ?