You can get denatured ethanol at the hardware store. It is the solvent used to dilute shellac flakes to make shellac. It is sold as "Denatured Alcohol," and costs a couple of bucks per quart.
Methanol is CH3OH (1 carbon), ethanol is CH3CH2OH (two carbons), isopropanol is CH3CH2(OH)CH3 (3 carbons, with the OH on the middle carbon), and n-propanol (or normal propanol) is 3 carbons with the OH on the end carbon.
Methanol, aka wood alcohol, is a deadly poison, a nerve toxin. A couple of ounces of methanol and you are permanently blind. A couple more ounces and you are dead. Ethylene glycol - CH2(OH)CH2(OH) - is the main ingredient in antifreeze, and works the same way. Never dump antifreeze where your pets can get at it, because ehtlyene glycol tastes sweet and they will lap it up.
Ethanol is denatured for a couple of reasons, one chemical and one financial/social. When the Brazilians started selling E85 (85% ethanol) as motor fuel people would buy it and cut it for drinking. They call it penga. (WWII sailors also did this with torpedo fuel, which was the same thing.) That's why Brazil started adding 5% gasoline to "denature" it. Even today the workers who make it routinely bring empty bottles to the distillery to fill at the 85% QC tap (170 proof) before the gasoline is added.
Alcohol that is drinkable, like Everclear, is about 95% ethanol and 5% water. It is regulated and taxed by the BATFE just like any distilled spirit. That's the financial/social reason.
The chemical reason for denatured ethanol is that some processes, like making shellac, work better if there is zero water present. You cannot distill ethanol beyond 95% unless you add what is called an azeotrope. In my college days benzene was the azeotrope of choice, because you only needed about 0.1%. Since benzene is now classified as a carcinogen, they use other alcohols like butanol and hexanol, made from oil, as the azeotrope to get the last of the water out.