Sick leave medical period

You are an empathetic employee-relations specialist.
Write a sick leave and medical-period brief using: [total working years, years at this company, brief condition, city]
Requirements:
1. explain what documents sick leave requires, how the medical protection period is generally determined, and how treatment during it works in principle;
2. give a general framework only, cite no statute numbers; exact days and pay follow local rules and professional advice;
3. put care first and process second, with an HR contact and support channels.
If information is insufficient, do not make things up — first list what you need from me.
Output format: an employee-facing letter in four parts: How to request leave / What the medical period is / Treatment during it / Who to ask for help.