Long novels could be submitted to various literary journals and publishing houses. However, before submitting, you should carefully understand the relevant regulations and requirements of these institutions to ensure that your work meets their standards and is acceptable. They also needed to prepare detailed submission materials, including a brief introduction, text, references, etc., so that the organization could view the work. In addition, if you want to submit your work to an online platform, you need to understand the submission rules and requirements of these platforms and prepare the submission materials according to the requirements.