Hoarseness of voice, progressive in nature should be checked with endoscopy as you have been told. However since its not possible in present scenario medications have been prescribed.
Do you have acidity problem? It can slso cause voice change
Next Steps
Pl locate clinic doing endoscopy and visit( additional cost of ppe may be included)
Alternatively CT scan of neck can give some insight
Health Tips
1. Give voice rest
2. Stop smoking and alcohol
3. Avoid spicy oily food
4. Start steam inhalation