If you are undertaking a systematic review, once you have established your question and developed your search strategy, you will need to create a protocol.
Your protocol is a proposal of the review you wish to perform, and a plan of how you are going to go about it. The protocol sets out the methods to be used in the review and provides an explicit plan for your work.
If you are undertaking a different type of study, you may have to create a research proposal which performs the same purpose as a protocol.
Your protocol should include:
Full details of what should be included in your protocol can be found in the PRISMA 2020 checklist.