Intelligent Investor and it's even denser cousin, Securities Analysis (both by Graham) are often touted as must reads without the recommender actually reading them.

I have read both and you can safely skip most chapters. I can summarize for you, that based on your description in this post, you are what Ben Graham calls a Defensive Investor, as you want to preserve capital without being able to make significant time or resources towards exploring companies in-depth.

The modern way to be a Defensive Investor is to invest 50-50 in a stock and bond ETF/index fund, such as VTI and BND. It provides broad, safe exposure that mimics how you would have done it in Graham's day. If in the future you find wanting to put the time into your investments, that is when I would consider becoming an Enterprising Investor, at which point you should read that chapter in II, and read Margin of Safety.