Use a small USB stick (under 32GB) and format it to FAT32 .
Artlii maintains an active customer service portal where they send firmware files via Google Drive or WeTransfer links based on your order ID. 2. Community Forums and Open Repositories yg300 firmware link
If you bought the projector from Amazon, AliExpress, or eBay: Use a small USB stick (under 32GB) and format it to FAT32