Unable to find C++ Classes folder in my content browser

What about the <project_name>.uproject,

Does it have the structure bellow, I mean, is there a modules section in it?

{
	"FileVersion": 3,
	"EngineAssociation": "5.5",
	"Category": "",
	"Description": "",
	"Modules": [
		{
			"Name": "Dev55",
			"Type": "Runtime",
			"LoadingPhase": "Default",
			"AdditionalDependencies": [
				"Engine"
			]
		}
	],
	"Plugins": [
		{
			...
		}
	]
}

If doesn’t, add it and regenerate your solution.

But if everything seems good and still doesn’t working, try this:

Hope that helps - take care.