Rendering 3D model , makes an FPS drop

Hello , as I said in title , i have a huge fps drop when see my 3d model in game.
This is the dynamic.
Model is behind a wall (i can’t see it) , when i walk into his face , my fps drops like -50 , then they go back to 60. If i will face that model again , it won’t drop again (till next play) . What is the problem here?
Is there some way to pre-load models?(like a loading screen which makes you load everything you need)?

I’m not sure whats your problem here but there’s a way to preload assets. Go to Edit → Project Settings → Player. Then in the Other Settings tab look for Preloaded Assets array and put your model prefab there.