This is the process of using nouns as verbs that has been increasing lately. Some call it denominalization, others verbing.
It’s nothing new — verbs have been created from noun forms throughout the lifespan of Modern English and perhaps even before it evolved from Middle English; what’s been different during our lifetime, perhaps, is the rate at which it occurs. (dailywritingtips)
This process particularly permeates all registers of language, and while using it unawares at times, it is often considered controversial and meets with opposition. Thought.co explains:
In a single workday, we might head a task force, eye an opportunity, nose around for good ideas, mouth a greeting, elbow an opponent, strong-arm a colleague, shoulder the blame, stomach a loss, and finally, perhaps, hand in our resignation. What we're doing with all those body parts is called verbing—using nouns (or occasionally other parts of speech) as verbs.
Theoretically, you can transform any noun in a verb.
Verbing is a time-honored way of coining new words out of old ones, the etymological process of conversion (or functional shifting). Sometimes it's also a kind of wordplay (anthimeria), as in Shakespeare's King Richard the Second when the Duke of York says,
- Grace me no grace, and uncle me no uncles.
Now, the boundaries you set to converting nouns into verbs is still subjective, and can vary according to culture, region, work environment. This site advises:
There’s only so much you can do to champion denominalization or to choke it, but in the end, it’s a democratic process: If a neologism appeals to you, promote it by using it. If it appalls you, demote it by eschewing it. Not every grating verbification will last, and if one that particularly annoys you goes extinct, you can take partial credit because it has always been absent from your writing.(dailywritingtips)
Some believe that in certain cases, using nouns as verbs is simply due to laziness when the speaker can't be bothered with grammar or vocabulary and chooses the easier way out, the way foreigners do when their poor knowledge of a language forces them to over-simplify their sentences.
It is true that people are using he wants to suicide nowadays, and I personally do find it unfortunate, as it looks casual, as James pointed out. I wonder if people do it influenced by other languages where the verb has always existed (se suicider -French, αυτοκτονώ - Greek, etc.)
I would recommend to use the correct expression.
He wants to commit suicide.
or, in fewer words,
He is suicidal.