PEMDAS is used for these kinds of problems so that you know what step to start with first.
P = Parentheses first
E = Exponents
M = Multiplication
D = Division
A = Addition
S = Subtraction
First Example:
Using the PEMDAS rule let's start with multiplication then divide then add.

Second Example:
Using the PEMDAS rule let's start with Exponents then multiplication then addition then subtraction.

Hope this helps!