Reading that it sounds like your core issue is around low self confidence.
Taking an IQ test might help to dispell the idea that you are below average. You might be under the LW IQ average IQ of 140 but you are probably well above 100 which is the average in society.
I can guess that my IQ has three digits. It's just that it doesn't enable me to do things better than others. Except solving iq tests, I guess.
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
To any future monthly posters of SQ threads, please remember to add the "stupid_questions" tag.