Blend Mode (Blend Mode / Alpha Blend) is a technical term that is extremely important in rendering and optimizing game graphics (technical art). When drawing a translucent object, a general term for settings that specify the formula used to mix the color to be drawn (source) with the color of the background already drawn on the screen (frame buffer) (destination).
Real-world analogy: Chemical reaction rules for synthesizing colors on paper with a black background using transparent cellophane (Alpha), a flashlight that illuminates the darkness (Additive), or multiple layers of paint (Multiply)
Blend mode is "a chemical reaction recipe that determines what kind of 'mathematical mixing (addition, multiplication, blending)' is applied to the underlying background paint when applying a new translucent color". You can create completely different worlds of light and shadow by simply changing the recipe, such as simply making it transparent (Alpha), emitting light and making it bright and white (Additive), or dyeing the back dark like stained glass (Multiply).
Illustration: Blend Mode (Blend Mode / Infographic that clearly illustrates the basic processing flow and mechanism of Alpha Blend) in Japanese notation
Detailed mechanism and operating principle
Change Shader Graph's "Surface Type" to "Transparent" and switch "Blend Mode" to either "Alpha (normal blend)", "Additive", or "Multiply" depending on the nature of the effect you want to create.