The most important skills children can acquire during early childhood development include: motor, perceptual, cognitive, literacy, language, emotional and social, mathematical reasoning, scientific reasoning, and creative learning skills. For more on this check out:
https://education.ohio.gov/getresources/publications/ohio%E2%80%99s%20learning%20standards/early-learning-and-development
and
https://thejournal.com/articles/2017/04/25/10-key-concepts-early-childhood-curriculum.aspx