ISO 45001: Support, Operation and Performance

Answer:
The first thing to note, is that Iso 45001:2018 does not require an OH&S manual, but you can choose to write one if you find this useful to collect your information. So, it is not a requirement to go through everything in the standard and say how you do it. The three main topics you are asking about cover the following sub-clauses in the standard:
Support – This clause talks about how you identify resources for the OHSMS, define and ensure competence for activities, raise awareness of the OHSMS, communicate both internally and externally and how you manage your documents and records.
Operation – This clause talks about controlling your operations through hazard elimination and reducing risks, managing change and ensuring that necessary OH&S information is part of your procurement activities. Further you need to plan for potential emergencies.
Performance evaluation – This clause talks about how you monitor a nd measure processes, perform internal audit, and conduct management review of the OHSMS.

For a better understanding of the clauses of ISO 45001:2018, see the whitepaper: Clause-by-clause explanation of ISO 45001:2018, https://info.advisera.com/45001academy/free-download/clause-by-clause-explanation-of-iso-45001