Can I design a level in photoshop?

Hello,
I didn’t a search in the forum about level, but many answers where 4 o more years old and I am not sure if it exactly what I want.I recently did a very simple test with cocos2d-x in c++ following some tutorials. Just a square jumping above spawing objects and getting scores. Very simple but a nice little introduction to start to get familiar with the api.

The thing is that I want to "handcraf"t a level, using photoshop for instance (or any other tool, I don’t mind). I don’t want to proceduraly generate levels. In the tutorial I did, obstacles where generated and assigned a movement from right to left. How would I do that with a whole level? This is my guess:
1-I create a huge image in photoshop where the width is the lenght of the level.
2-I cut the level in sprites that will have set a physical body, so the square hero can jump around ( so it is just a constant plain floor)
3-I create individual layers for each enemySprites and position them around the level
4-I attach everything to a null pointer so the whole thing moves from right to left (kind of like the geometry dash).

Am I on the right track?
I am trying to avoid any editors. That’s why I chose cocos2d-x, because I love to code: I don’t enjoy creating a game with editors that’s why I didn’t use unreal, unity, ore even cocos creator.

So is that correct? In summary: Create the map in photoshop, cut it out in sprite and position them one next to the other by coding their coordinates, attach all to a null and make it move from left to right.

By the way, how do you create a collision mask for a more complex sprite, for instance with diagonal edges, or curved surface? Is it also with PhysicsBody?

Thanks

Photoshop, blender, illustrator, Gimp, MS Paint, etc

Check out Texture Packer and their related tools.

Check out Tiled Map Editor.

thanks for the quick response. About the development of that type of game that I mentioned, is that the correcto aproach? attach all the sprites except the hero to a null, and make the null move from right to left, and if the character jumps, make the whole scene go down? something like that?

There is no correct answer. You are the developer. Write what works for you. As you gain experience, refactor.