That’s a good, well-written guide. It mostly ignores exceptions and special circumstances, but that is appropriate for the target audience.
It’s not a guide. It tells people to buy one gun - a revolver.
On a side note, in the 1980s, my grandmother told me to look in the side cabinet beside her bed and to take the pistol home with me, because she was too old to even pick the thing up (she could barely hold a fork). Not even knowing there was a pistol in the cabinet, I found a beat-up S&W 1917 (a revolver made during WWI and chambered for the 45acp.). My grandfather had put it there when he went off to fight in WWII (1942). My grandmother had never touched it. So I took this 60+ year old pistol that was loaded 40 years earlier to the range. Without even dusting it off, I fired all six shots off without a hitch.