"Please help me a little bit."
Yes, it's another bad translation. "Please help me a little bit" should be "请帮我一下。"
But "please help a little bit" normally means the same.
It should be 请帮我一下 or 请帮帮我， because duplicating the verb makes it less intense out to mean "a little". Besides that, there is not enough context here to lead me to the correct answer. It's not like they translate the words ahead of time, just their sounds.
I'm not a native speaker, but my understanding is as follows:
一下 is a little bit of time.
ex. wait a while: 等一下
ex. a quick look: 看一下
一点 (儿) is a little bit of something other than time.
ex. a bit of water: 一点水 (before nouns)
ex. a little cheap: 便宜一点 (after adjectives)
((Side note: 一些 (Yīxiē) also means "some" (ex. some water: 一些水) but is only used with nouns.))
When teamed up with 有(Yǒu) 一点 can also be used to express "a little too..."; 有一点 (儿) shortens to 有点 (儿) and comes before the adjective.
ex. 有点贵 = a little too expensive
I hope this helps, but I recommend AllSetLearning for more info on 一点 and 有点.
一下 does not have an equivalent in English, we simply put it after verbs(in action) to soften the tone and make it sound less like an order. In this case it doesn't really matter whether you translate it as 'one moment' or 'a little bit'-whatever suits you the best.