Trouble with Equation (Evaluating W/ Fractions and Decimals)

Hi!  This question is based on this video: https://youtu.be/GmD7Czmol0k  and I am currently on the Foundations Level of Algebra (here)

https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:substitute-evaluate-expression/a/evaluating-expressions-with-two-variables-with-fractions-and-decimals?modal=1

I am so confused about how to do the algebra with the fractions!! What do I do? Write them as a decimal? I was able to figure out the first fraction in the video...  You divide the 12 from the four (because it's 1/4- you divide from the bottom- just like you explained in the video)

But then on the practice page, Khan gives us 3/2 (4) - 3 + 5/3 (3). Is there a video breaking down how to figure out how to solve the fraction part of the math problem when it's not as easy as 1/4... Now I'm working with 3/2 and I am all sorts of confused!

I'm studying for my math praxis and math has never been my strong suit. (Hence why I am starting at the very beginning)

I hope someone sees this! THANK YOU!!!

Alicia