Meshes Imported from Blender Problem

Development Asset Creation
1

Hello guys, I have been using unreal and blender for almost 2 weeks now so I dont really know most of the terminology.
I have come across a problem when importing meshes from blender to unreal. My problem is that I have created a mesh in blender
and when I switch to edit mode it looks ok ( I think)(image1), I export it as a FBX file,but when I import in unreal i get 3 messages:

1=no smoothing group was found in this FBX scene (I have searched how to fix this but could not)
2=cube has degenerate tangent bases (could not fix this either)
3=has some nearly zero bi-normals (not fixed)

When I ignore these messenges and drag and drop the mesh (it has 5 different meshes) and then add materials on it
the material looks stretched(cant find a better word) and sometimes it trembles. (image2)

Could you please help me find a solution to this problem, I started a project for fun but I am really into it as the time goes by
but I cannot continue because of this problem.

As I said, I dont know the terminology yet and english is my second language, so if you have an answer write it step by step
as if you are talking to a child, for example “right click then click edit…etc” or if you have a tutorial video which can help.

Thanks for your help.

2

It seems like most of the problems have been solved but there is something new happening as you see in the images. Because I didn’t know how to make the shape of this column thing(don’t know the word for it) I created it like this:

I created a sphere and then extracted and scaled down its edges again and again until it looked like you see in the picture. It doesn’t look that bad for what I want to use it but when I import it to unreal some of its faces dissapear. I have tried exporting it with different export options at the export tabs like geometry, but it I cant fix it.

The only solution I was able to find was duplicating it then rotating it 90 degrees and join them together, but as the second friend replied,the mesh flickers.
Thank you so helping.