If your home screen is empty, your NAND file doesn't have the DSi Menu installed. You may need to perform a "System Update" within the emulator if your firmware allows.
Below is a detailed breakdown of what these files are, why they are needed, and the safest way to acquire them. dsi bios files download
Note: DeSmuME has limited DSi support compared to melonDS; most users prefer melonDS for DSi-exclusive titles. ⚠️ Important Legal Note If your home screen is empty, your NAND