How do I smooth out my model

I am currently trying to make a csgo like butterfly knife, and so far its not going to badly. However my model isn’t really “smooth” like I want it to be.
Here is what it looks like

How do I fix this

If you mean smooth the geometry, subsurface could help, but it will smooth edges you dont want to smooth also. This tutorial might help you. If this doesn’t answer your question please elaborate on your question. What you would want to do is subsurf, but highlight the edges you dont want to smooth and mean crease those edges you dont want smoothed with the mean crease setting in Properties Panel (open with N) and again this only works if the subsurf modifier is active

If the above video doesn’t help you I would probably be willing to make a second one more specific to your usage case.

Made a vid to help you out, feel free to give me a reference photo if there’s a part you can’t figure out how to model.