The dictionary explains this as:
To show somebody that you are interested in them and/or want to help them
The explanation indicates the subject of the sentence is the one that offers help, but I think this one is also correct:
I'll try it first, and if I can't handle it, I'll reach out to you for help.
I am confused about who offers help because I saw my native speaker colleague write this in an email:
Thanks for reaching out to me.
Is this a "thanks" for helping or being asked to help?
Best Answer
The definition shown in your dictionary is unnecessarily narrow, which has led to your confusion. More broadly, "to reach out" means to initiate contact with someone, with the usual implication that the contact is helpful or beneficial.
For that reason, either the helper or the person requesting help can be said to "reach out" to the other. The only stipulation is that the subject of "reach out" is the one who initiates the relationship. If you ask someone for help, then it is correct to say that you reached out for help from them; but if they offered help without you asking, then they reached out to help you.
(Note also this difference: you reached out for help, they reached out to help.)