What is the difference between these two sentences?

Thanks for this post.

"Bro's onto something" = he has done or discovered something significant "Bro's on something" = he is under the influence of drugs

Bro's onto something: Bro has figured something out Bro's on something: Bro is on drugs

Being on something means being under drugs

Bros onto something implies they have a good idea or are doing something right. Bros on something implies drug use

First let's be clear that they omitted the ' in *bro's* which may add to your confusion "bro \[is\] onto something" = bro has realized an important insight "bro \[is\] on something" = bro literally took drugs and is only saying this because he's high

If someone's onto something it means they are doing/thinking something smart. If a person is on something they are on drugs (the phrase implies illegal ones). So instead of them being smart or innovative they are acting stupid/high.

If you are 'onto something' it means that you have made a discovery that will lead to a positive outcome. Another similar and common one is 'on the right track.' If you are 'on something,' that something usually is in reference to drugs. The comment is essentially saying "This person is not making any grand discoveries, and it is as if he's on drugs" indicating that the individual in question must be confused or stupid.

If you're ONTO something it could mean: 1) you have realized or created something could be a very good idea. eg. Mike has created a dating app for lonely pet owners. He's already got 10,000 downloads so it looks like he is ONTO something. 2) They're ONTO us = our actions (usually bad) have been discovered. Mum's ONTO us - she knows we ate her favourite ice cream. If someone is ON something, it usually applies they are taking something, ie. drugs. The person may not actually be taking anything but they are behaving weirdly or nonsensically.

Being onto something means having the right train of thought/an interesting thought that may be “correct” On something is under the influence of something, it can also be use sarcastically if someone is being stupid or acting like an idiot.

Onto /on , literally wasn't aware of that ..

In this context, "Bro" seems to have made some kind of claim, probably a conspiracy theory. "Onto something" would mean that the poster thinks that "Bro" has indeed uncovered evidence pointing to the conspiracy theory being true. "On something" is a statement suggesting that "Bro" has taken some kind of drug and that their conspiratorial beliefs are the result of the drugs inducing an altered mental state (hallucinations or paranoia).