I'm guessing that your problem comes from trying to translate the Spanish word 'como'. Most of the time 'como' translates as 'how'. For example: How are you? How does he travel to work? How do you say this in English? I don't know how to thank you. She taught me how to ski. I'm also guessing that your confusion comes from the fact that a phrase like 'tan grande como sea posible' is 'as big as possible' in English. Is this your problem? If so, just remember that we use 'as... as' (NOT 'how') for comparatives of this type: I'm not as tall as my brother. Bring as much money as you can. I've studied as hard as you have. I hope that helps.

How is most often used to ask a question: How tall are you? How old is that fence? How can I get a cat? Then there's examples like this: I don't know how to work. He doesn't know how to sing. As is usually a comparison word: He is as furry as a cat. She is as bright as the sun. We are as purple as an octopus. Hope that helped!!~~ :)

almost same but it depends ur intention. mostly how is used in questioning but as is used like saming something,