java - 3D block model for Minecraft works as item but becomes a

I have a block that is a 3d model that's going to be similar to a skull. It renders the model as a item but when I place it it becomes a null block. Originally it was going to be a armor piece but

3DItems SpigotMC - High Performance Minecraft

teyokuma's 3D Item Models for 1.15-1.20.1

The World Generation of Minecraft - Alan Zucconi

PureBDcraft for Minecraft Java Edition

Help please java 3d block model : r/Blockbench

Modding By Kaupenjoe: Forge Modding for Minecraft 1-18-1, Kaupenjoe (Nico)

Minecraft - Wikipedia

I was trying to import my blender model into blockbench for the first time but whenever I try to convert it to a java block/item nothing happens it just goes blank

My new mod called Items Displayed, which allows you to place items as 3D models : r/feedthebeast

teyokuma's 3D Item Models for 1.15-1.20.1