In order to specifically express that one thing happens/begins to happen after another thing,
てから will be used. This expression is regularly translated as 'once (A) happens, (B)', or 'after doing (A), (B)'.
おやつを食（た）べてから、勉強（べんきょう）を始（はじ）める。
I will start studying once I eat some snacks.
洗濯（せんたく）をしてから、出（で）かける。
After doing the laundry, I will go out.
The difference between
てから, and the regular
て form followed by another verb, is that
てから puts more emphasis on the (A) action 'enabling' the (B) action.
から can come after almost any form of verb.
てから is the only form that translates as 'after (A), (B)'. た
から, and
るから will translate closer to 'because', or 'since'.
今夜（こんや）は勉強（べんきょう）をするから、遊（あそ）ばない。
I won't hang out tonight, because I will be studying.
牛丼（ぎゅうどん）の大盛（おおもり）を食（た）べたから、お腹（なか）いっぱい。
I am full because I ate a large serving of gyudon. (After having eaten a large serving of gyudon)
晩（ばん）ご飯（はん）を食（た）べてから、洗（あら）い物（もの）をする。
After I eat, I will do the dishes.