To get ISO 27001 certification, the organization has to maintain a documented system according to the ISO 27001 requirements. The following information is required to before applying for ISO 27001 certification:

Determine the scope of your organization’s data that is valuable and needs to be safeguarded
The first step in safeguarding your vital information is to conduct a risk assessment
Develop policies and objectives for the Information Security Management Systems
A detailed plan to treat the identified risks of the ISMS
Risk assessment report
Results of monitoring and measurement
A detailed program for an Internal Audit of the ISMS