な can be used to make a very forceful command. Probably from negative form (〜ない). It is also sometimes used in slogans.
動くなよ Don't move!
変なことを言うな！ Don't say such weird things!
Sometimes causes contractions
それを食べんな！ Don't eat that
can refer to what has been said in the past.
十時以降はテレビを見るなって言われたんだ。 I was asked to not watch TV after 10 in the evening.
When asked to not do something,
Can be made softer with combining with って for a quotation.
無理すんなって Don't overwork yourself.
https://www.tofugu.com/japanese-grammar/na/