Adding texture to the Model?

Question

Blender

The thing is, I have a folder. It contains the OBJ model itself and another folder with a large number of textures for OBJ .
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I have a model of a soldier from the game R6. And the textures on his specific part of the body, be it a helmet, boots, hands, etc.
When I want to add, let's say a helmet, when I select a model's head, I have the whole model selected. And when adding the texture of the helmet, this is what happens:

Doesn't everyone know how to solve this, it's not just that these models are scattered in a folder.

PS I've been looking for an answer for 3 days now.