Car starting issue

I recently regained possession a 1992 240sx that I had given my brother-in-law. Needless to say he trashed it and I have to fix. But that’s another story. However it does not start unless you push start it. If you turn the key all the electronics work except it will not start. Nothing. No noise, just nothing. I had an old starter around and changed it out still no go. The ignition switch is very loose and I am leaning towards replacing it next. Is there any way to test it before I try figuring out to take it apart because I have never done that. The battery seems to be charged up also. Is there anything else I should check first?