as well as - Also. as good as - almost same

Good is an adjective. It gives us more information about the noun. "It's a cake." "It's a GOOD cake" Well is an adverb. It gives us more information about the verb. "Josh plays tennis." "Josh plays tennis WELL." You use "as good as" when you talk about quality. "This cake is not as good as the other one." NOT "This cake is not as well as the other one." - this is wrong You use "as well as" when you talk about a skill, performance etc. "Peter plays tennis as well as Josh." NOT "Peter plays tennis as good as Josh." - this is wrong (but you might hear people use it) There is a funny scene in the movie Zoolander where they're discussing the possibility of opening the "Center for Kids Who Can't Read Good". It's funny because they want to teach children how to read, yet they make a mistake in the name of the institution.

"good" is an adjective, and "well" is an adverb. Use "good" with nouns. For example, good car, good book, good job, good food, etc. Use "well" with verbs. For example, works well, runs well, speaks well, etc. So, use "as good as' with nouns. For example, "My car is as good as yours.", "My new job is not as good as my old job". And use "as well as" with verbs. For example, "you speak English as well as I do", or "I want to speak Japanese as well as you do".