The order of operations always applies in equations. I like to remember the order of operations as:
Please Excuse MyDear AuntSally or Parentheses (Grouping Symbols), Exponents, Multiply/Divide left to right, and finally Add/Subtract left to right.
It appears in your problem that there are no exponents, which are little raised numbers to the right of a regular number. In computer, we usually write it as: 4^2, which would mean 4 times 4 which is 16.
In your equation, it looks like you are supposed to put in grouping symbols or parentheses. In order to get 192 as the answer, you would place the parentheses like this:
(36-4) x 6
32 x 6
Without any grouping symbols, you must follow the order of operations, which would mean that you would multiply first, then subtract:
32 - (4 x 6)
32 - 24
But that doesn't yield your required answer of 192.
I hope that clarifies what you need to do first.