The only officially "safe" way to obtain a BIOS file is to dump it from your own physical PlayStation console using specialized hardware or a modded console.
Ensure your BIOS region matches your game region. While some emulators are "region-free," using a US BIOS with a Japanese game can occasionally cause glitches. ps1-rom.bin bios
The Ultimate Guide to the PS1-ROM.bin BIOS: Everything You Need to Know The only officially "safe" way to obtain a