In your example, only the singular is possible. A range of ages ("from age 1 to age 2") starts at one age (singular) and ends at another. We can also talk about the period between a pair of ages (plural).
During the period from the age of twenty to that of thirty, the
mortality was eight per cent.; from thirty to forty, thirteen and one-
tenth ; from forty to fifty, thirteen
From the age of twenty to the age of forty, Bessemer lived the life of
a journeyman inventor.
The law also imposed penalties on orbi, that is, married persons who
had no children (qui liberos non habent, Gaius, ii.111) from the age
of twenty-five to sixty in a man, and from the age of twenty to fifty
in a woman.
Every Frenchman therefore is a member of the army practically or
potentially from the age of twenty to the age of forty-five.
A man from the age of twenty to sixty shall pay twenty-five dollars;
It took me from the age of twenty to twenty six to finally realize I
could be a good husband to the woman I loved
Way back in 1908, Kreisler (in an interview) said in the October issue
of The Strad 'I am thirty-three now, and from the age of twenty to
twenty-seven I struggled
Sunglasses are one of the only pieces in a gentleman's wardrobe that
he can have from the age of twenty to sixty without having to change
Best Answer
If you're in an argument about this, well really you could invent an argument either way. Either way, the argument you invent would probably sound convincing on the surface. Your argument that you "should" use a singular verb will probably hinge around the fact that "one" is singular. Your argument that you "should" use a plural verb might hinge around, say, the fact that it is ungrammatical to say 'A lot of people has...'.
But linguistically, these arguments are generally spurious. Like the argumentation behind many prescriptive rules, they appear at first glance to work logically because they assume a model of language which is overly simplistic. So if you say, e.g. that it "must" be a singular verb because 'one' is singular, really what you're saying is 'my model/understanding of how language works is too simplistic to take account of the fact that sometimes a superficially singular noun is actually part of the subject of a plural verb'.
If you look at actual usage, you will see that it varies. As a native speaker, my gut instinct would be that the plural is more common in spontaneous/informal speech, and that the singular is essentially a prescriptive invention. But I don't actually have any data to support that. (I'm guessing even some of the small available corpora such as Collins Cobuild might provide some data if anyone has time to look at this.)
Peter Shor shows a case where preference for the singular verb apparently overtakes the plural. However, note that the phrase he has chosen uses ellipsis (it "misses out the noun"). If you do some other Ngram searches including the noun, you can find answers where the plural overtakes the singular (e.g. "one in five people have/has"). I'm not sure that Ngram in this case gives a very reliable overall picture of general usage, though it does clearly indicate that both forms are used.