if you want to import your models into blender you will first need:
1: blender (duh)
2: any source 1 game (examples would be counter strike 1.6, portal, half life and its expansions etc)
3: crowbar (the tool not the weapon lmao)
4: blender source tools (second most important thing after crowbar)

if you have spent more than 5 seconds in blender you must've noticed its not as simple as just importing the source models (and if you dont then oops i just spoiled it) and thats where crowbar comes in
with crowbar you will want to

1: select the model

2: select the place where the decompiled model will end up in

(optional): change the settings (optimally you want to use my settings bc they order stuff in folders)
3: press on decompile


now you have a decompiled model that is a whoooole lot easier to import

now you may have the decompiled model ready but blender isnt ready as you still cant import any of the decompiled stuff, and thats where the blender source tools or whatever its called comes in

step 1:download the blender source tools but DO NOT UNZIP THEM YET
step 2: go to blender and into the install tab of the addons tab in the preferences tab (god that is long to say)

step 3: now you can unzip it and put it in blender


after having done all of that the tools should be ready and you can now import the decompiled model

now that both the decompiled model AND blender are ready you can begin importing the model

step 1: use the blender source tools in the import tab

step 2: look for the model's .smd file (in my case its the half life smg)

step 3: import the model (duh)

congrats!!! you just imported a .mdl file succesfully into blender!!!, but theres still stuff to do

(probably) step 1: re texture the ENTIRETY of the model since at least for me it came without textures and its very yucky
step 2: uhh actually theres no step 2

after you have done whatever you might have done to the model (adding a horse head, retexturing it or making a ♥♥♥♥♥♥ guide on how to do it) you will eventually be tempted to do one out of 2 things

option 1: using your new and improved model in-game
step 1: literally do the exact same thing as decompiling the model except its on the compiling tab and not decompiling

option 2: stealing it for another game engine that doesnt use .mdll
step 1: make sure the model is not ♥♥♥♥♥♥ up in any way and its not going to look un textured/badly textured
step 2: export the model and then import it into your game engine

you have just imported your source engine model into blender!!!, now you have full access to do whatever the ♥♥♥♥ you want it with such as giving it funny textures or weird scaling or just steal it for your own game, the file size is the limit!!!

nobody lmao i did this all by myself (hence why its so ♥♥♥♥♥♥♥ bad)