Sometimes changing your routine or going on an adventure can do the trick. New experiences can fuel your imagination. And don't be afraid to dream big; let your mind wander and see where it takes you.
You can get inspired by reading a lot of different books and observing things around you. Maybe a beautiful landscape or an interesting person could spark your creativity.
Begin by immersing yourself in the text or novel. Absorb the mood, the tone, and the overall feel of it. Once you've done that, decide on the genre of your book. If the source material is a horror novel, and you want to write a book inspired by it, you could choose to write a horror - themed book as well. Then, start writing, using the inspiration from the text or novel to fuel your creativity. Don't be too rigid in following the original; let your own creativity flow while still maintaining the connection to the source of inspiration.
First, research is key. Learn about Afghan history, its different dynasties, cultural practices, and the daily life of its people. For example, study the Timurid Empire which had a great influence on Afghan art and architecture. Then, decide on your time travel mechanism. It could be a magical amulet or a scientific experiment gone wrong. Next, create a relatable protagonist, perhaps an Afghan - American who wants to discover their roots. Let them experience the beauty and the hardships of Afghan history.
Read a lot. Reading different genres, styles, and authors can expose you to new ideas, themes, and ways of storytelling. For example, if you read a mystery novel with a unique plot twist, it might inspire you to create your own mystery with a different kind of twist. Also, observe the world around you. People, their relationships, and daily life events can be great sources of inspiration. You could base a character on someone you know or create a fictional town based on a place you've visited.
Look into history. There are countless events, figures, and eras that can fuel your imagination. For instance, the Renaissance period with its art, science, and social changes can be a rich source for a historical novel. You could also join a writing group or workshop. Interacting with other writers, sharing ideas, and getting feedback can inspire you to come up with new concepts for your novel.