There are different methods for solving a word problem such as this. If you have learned how to solve two equations in two unknowns, then you might start by writing stuff down, like...
Let x be the larger number.
Let y be the smaller number.
Now your next step is to take the information given to you in English and translate it into Math.
You say "One number is 8 more than another." Using the information about x and y, write a mathematical statement (equation) that says "one number is 8 more than the other" keeping in mind that y is the smaller number and x is larger. The "is" is the equal sign. More than probably involves addition or subtraction is some way.
After you have that one, write a second equation that says "the sum of the smaller number and twice the larger number is 46". Now you have two equations. Solve them simultaneously. If you need more help, show us how far you got so we know how to help.