Are there any errors in the sentence?

It’s grammatically correct.
Use Suffering.
Be creative as you want for the title.

Are there two articles that require capitalization? Is Joy and Happiness another article? If not, it shouldn't be capitalized.

Title of books,articles, and papers are subject to a convention known as "title case" where important words are capitalized.

(see Title Case Converter)

The title would be correctly written this way:

Suffering and Hardships Will Enable Us To Develop Joy and Happiness

I would say either suffering and hardship or sufferings and hardships.

I prefer the former.

The way it's written and capitalized looks like that there are two articles. That's what is confusing.

1. Learn the title case rules or use a converter in the style you require. https://capitalizemytitle.com/

2. The other abstractions are singular.

3. The title (not a sentence) implies that S & H is an essential precursor and imperative concomitant to J & H, which is contentious.

Perhaps a dichotomy would tantalise the reader and be more precise.

Suffering: Hardship :: Joy: Happiness