How to choose a lamp when designing lighting?

What is required illumination - determine the number and luminous flux of the fixtures and their type. I assume that at this stage you already know which lighting scheme you chose - combined, general or local.

Power, since you have already decided on the number of luminaires and the luminous flux of each of them, you need to determine what power the lamps should be in and what type (LED DNaT, DRL, fluorescent, etc.), so you can already check if the available on sale fixtures to realize your project with so many fixtures at their specific power. Are there luminaires more powerful or weaker, is brightness adjustment (dimming) available.

Directivity or “light intensity curve”. When you determined the type of fixtures (4x18 or 2x36 linear fluorescent raster, or decorative chandeliers, well, or spots) - determine how much diffused or directional light they should give, in accordance with your lighting scheme.

I also recommend watching how others do it - for public places they often use linear fixtures such as fluorescent 2x36 or raster 4x12 - this is a universal and convenient solution. For industries and on the street, there are often Cobra lamps, or spotlights. Also, lamps of the “RSP” type, well, or as I call them “inverted bucket” ...

For a home interior or of the same theaters, cafes and the like, trends are constantly changing. 10 years ago they loved spotlights, but now they love either flat LED panels or some kind of chandelier.