Hi Belwong, an employee handbook is basically like an induction/orientation book or manual that is summarized in a booklet. Depending on your requirements as per HR policy, you can create that handbook. You may need to create a framework as per your HR policies. Just to start, you can outline a framework with content as follows:
1. Company in brief - history and snapshots
2. Some important labor rules (this has to be specific to the country where they are working)
3. Health and Safety - especially in fire safety and evacuation
4. Sample copy of an appointment letter and explanations of each item in the appointment letter
5. Other important documents that an employee needs to know that will be in their personnel file
6. Salary gazette or rules and regulations provided by the government regarding compensation and benefits
7. Do's and Don'ts - mostly zero-tolerance policies
Importantly, it's only a handbook (can fit inside an employee's pocket). Thus, all the contents must be brief but comprehensive and easily understandable by the reader. You may add more if you feel it will be required.
I hope this helps in some ways. Good luck!