You can download plugins from the official ePSXe website or other trusted sources. Some popular plugin sources include:
(GPU, SPU, CDR) — some are open-source (e.g., Pete's plugins, PCSX2 GPU plugins). Official ePSXe plugins may be included with the emulator download.
The BIOS is the system software required to boot PlayStation games. Recommended Version: SCPH1001.bin