Excellent question, highlighting as it does a key literary period. Before starting my answer, I have included some links below that you may find helpful in answering your question. To understand Romanticism one of the best ways is to read some of the works of the Great Romantics such as Wordsworth and Coleridge. A key word to focus on is nature. To understand the concept of nature in the poetry of Wordsworth and Coleridge you need to understand that Romanticism was a kind of revolt to Classicism - the literary movement that came before Romanticism. Romanticism therefore moved away from focussing on reason and man's ability to work out situations and focussed more on the restorative power of nature and how it provides balm to us as mankind. Key to the poetry of Wordsworth is the location of the Lake Distict in England, UK, a place of great natural beauty, where Wordsworth in particular spent lots of time. You may want to read poems such as "Tintern Abbey" and consider what it says about nature. These pointers combined with the links below should help you towards an answer.
This question has already been asked and answered here on eNotes. Here are a couple of links for you:
Romanticism as a literary movement marked a period when authors, and society in general, became much less trusting of the church and other institutions and much more interested in recognizing the worth and power of the individual and individual experiences. Enhancement of personal perceptions through use of drugs became acceptable, dreams and visions were recognized as being significant and worthy of serious consideration and interpretation, and emotion was considered more important than intellect. Reflecting many of these viewpoints, poetry was the favored form of writing during the Romantic period.
Prominent authors of the Romantic movement include Jane Austen, Sir Walter Scott, Samuel Taylor Coleridge, Percy Shelley, and William Wordsworth.