There are still some good resources you can use. I would start by reading this guide to implementing 2D platformers
. As you will see, you have a lot of decisions to make. You have to decide what "type" of platformer you want to make (as described in the guide), you need to come up with characters, you need to decide on the details of the gameplay (how fast will the player's character move, how quickly will it accelerate, how high will it jump, will it be able to have some control of the movement while it's in the air, etc.).
You should break down the task of building the 2D platformer into smaller steps. Here's one possible plan:
* Put a blue rectangle on top of a floor and allow the user to move it around using the arrow keys.
* Make a scrolling background, which you can control with the left and right arrow.
* Improve the scrolling background to have multiple layers at different distances, with transparency.
* Add some platforms to the scrolling demo.
* Get your blue rectangle to be able to jump onto the platforms.
* Play around with the camera.
* Add some enemies (red rectangles are fine).
* Implement collision detection and response.
* Replace the colored rectangles with animated characters.
* Add music and game noises.
* Think of a format to describe a level in and write code to read that format. You might be able to find a format for which other people have written editors. If not, you may have to roll your own, although you can start by writing the files "by hand" to get started.
These steps are challenges that should be fairly manageable. If you have no idea how to approach them, perhaps you need to learn a bit more programming before you can tackle your 2D platformer.
Tutorials are a quick method to get you started with a language or a library. Putting together a platformer is probably too complex a project to cover in a tutorial.