Life size planets (making a planet i can land on)

So i am currently working on a space shooter type game as just a personal project, and i have searched google for around 13h searching for an answer.

So, my question is, is there a way of making a planet that i can land on and walk around on, but also take off and fly around the planet? I have tried using a spherical earth map converted to a HeightMap, but again, have come to no solution. Here is the look im going for, i dont necessarily need the water, i just really need the land mass. XNA Planet Renderer - Terrain & Ocean - YouTube

Have a look at these links:

They can be done with or without water, and use procedural generation for the land mass, so you get a different result every time.

You’ll also need to come up with a solution for spherical gravity for the planet, and for that I would take a look at this link: