In "Radical Lookup method", it's well known that we first identify the radical of the character and then look it up according to the number of strokes and so on. This method works well for characters like 休 and 银 Because in these characters, radicals are identifiable. My question is, how should one lookup characters which don't have any radicals like 电，天，多 etc.
All characters have "radicals."
电 (radical 102, 田...)
天 (radical 37, 大...)
多 (radical 36, 夕...)
Knowing what they are is a slightly trickier endeavor.
Slight objection - "A Chinese radical or indexing "component" is a graphical "component" of a Chinese character under which the character is traditionally listed in a Chinese dictionary." Certain words do not have radical simply because they are already in their simplest form (no component) and they are the radicals themselves.– r13Dec 15, 2021 at 18:04
电 = 田 (radical 102) + 0
天 = 大 (radical 37) + 1(一)
多 = 夕 (radical 36) + 3(夕)
You can copy and paste the word in the internet search bar, it will bring up the web pages that provide all information regarding the word.
Also note, each of the radicals above is a word itself. So for a word that seems already in the simplest form, it could be a "radical".