The next resource I would recommend is an e-book:
Title: Basics of Space Flight
Author: Robert A. Braeunig
This is an e-book I found a long time ago. From the author's description:
This Web page can trace its roots to the author's project to write a computer program simulating the launch of a rocket to orbit. As I performed my research it became apparent that most information on the subject tended toward one of two extremes: it was either too simplistic to be very helpful, or it was advanced texts written for engineers.
After spending months digging through books and Internet sites I finally found the information needed to complete my project. Not wanting others to go through the same frustrating search, I decided to organize all the information into a single resource. Thus, in 1996 this Web page was created.
I would recommend reading carefully through these topics in the Orbital Mechanics section of the website:
Conic Sections
Orbital Elements
Types of Orbits
Newton's Laws of Motion and Universal Gravitation
Uniform Circular Motion
Motions of Planets and Satellites
Launch of a Space Vehicle
Position in an Elliptical Orbit
Orbit Perturbations
Orbit Maneuvers
Orbit Altitude Changes
Orbit Plane Changes
Orbit Rendezvous
Delta-V Budget
The Hyperbolic Orbit
If a web search doesn't come up with this website, please feel free to message me as I have saved a copy of it
This chapter in my outline covers the basics of the scenario of a spacecraft orbiting a large body like planet Earth. There is a second chapter in the book called Interplanetary Flight, but I would recommend coming back to this later.