The gold standard for this issue is the GTA SA Widescreen Fix. It doesn't just unlock 1080p; it fixes the UI scaling so your map and health bar aren't stretched horizontally.
The original game was designed for 4:3 CRT monitors. Without these files: The image is , making CJ look wider than he is. The FOV (Field of View) is cramped. The HUD elements (radar, weapon icon) become oval-shaped. gta-san-andreas-1080p-resolution-fix-file
Drag the contents of the scripts folder and the dinput8.dll (the ASI loader) directly into your main game folder. The gold standard for this issue is the