Hi GameLover164!
First, you'll want to properly prepare your models by making them into a fairly universal format, such as .dae or .obj. For this, you can use a program such as
Noesis or Blender and export the model as the proper format.
From there, import the model into a program such as Maya or Blender and render a 148 x 125 px icon for use with the model. While you're at it, render a bigger, 750 x 650 px icon. Make sure to save the renders as a .png.
Then, place the model and corresponding textures into a single folder, and then compress the folder into a .zip file.
Next, go to
The Models Resource and navigate to
PC / Computer >
B >
Bendy And the Ink Machine. At the top of the page, you'll see a big green plus icon with the caption "Add New Model". From there, title your submission, select the .zip file you created under the "Model" section, the .png file you made for an icon under the "Icon" section, and the bigger .png file you made for a big icon under the "Big Icon" section. Finally, select or create a proper section for the model. If you have any specific notes for the admins about your model, leave them in the "Notes" section.
Hope this helps, cheers!