Hmmmm, where to start?
Make sure your battery is well charged.
If that doesn't do it, suspect a bad starter solenoid.
To test a starter solenoid, connect a test light to its output terminal then see if it has current. If the light comes on, that tells you this IS power going to the solenoid. If the light does NOT come on, check your battery!
Once you know you definitely have power, see if that power is being transferred properly by switching the red lead to the solenoid’s lower terminal.
Here is a video. Hope that helps!
https://www.youtube.com/watch?v=MsvJMnpQBas