When we have a habit of doing something, how do we make a sentence? He is habitual of drinking alcohol. Does it sound fine?
Actually, there is a specific verb tense that implies a habit, the simple present. Context plays an important role in this implied meaning, but on their own these sentences would certainly convey the idea that someone has a drinking habit:
He drinks a lot.
He is a heavy drinker.
No the standard form is he has a drinking habit, or he has a habit of drinking. The latter being more kind while the former indicates alcohol abuse. And if that's the case one would simply say "he's an alcoholic". https://www.aa.org