1: 'As' can mean 'because/since'.
- As it was raining, we didn't go out.
- As I was walking down the street, I saw Jimmy.
- James loves pets, as do I.
- John loves spicy food as much as I do.
- Lily travels as much as me.
- She's as clever as her sister is.
- London's not as big as Mexico City.
- She works as a teacher.
- Don't use the knife as a screwdriver.
I work like a waitress.
1: 'Like' can be used to give examples. It means the same as 'for example' and is usually followed by nouns or pronouns.
- Western European countries like France and Spain have high unemployment at the moment.
- John loves spicy food, like me.
- Tokyo is a busy and exciting city, like London.
- She looks like her mother.
- It looks like rain.
- That sounds like a car.
- The kitchen smells like lemons.
'Like' vs 'as' for similarity
Often, we can use both 'as' and 'like' to talk about similarity.
- I love coffee, like Julie.
- I love coffee, as Julie does.
I love coffee, as Julie.
- As your mother, I'm telling you not to go out now. (I am your mother and I am telling you this in my role as your mother.)
- Like your mother, I'm telling you not to go out now. (I'm not your mother, but I am telling you the same thing as she is. I am acting in a similar way to your mother.)
- She works as the manager (= she is the manager).
- She works like the manager (= she isn't the manager, but she works in a similar way to the manager).