Great questions!
When you're starting out a foreign language, your only frame of reference is how your own language works. So, when you're trying to say an English sentence in Spanish, it's perfectly natural to want to translate each word by its dictionary definition and form a sentence that feels comfortable to you as an English speaker.
Unfortunately, in most situations, you can't. That's why online translators do such a poor job. All languages have their own unique sentence constructions and ways of saying things that seem to us to have no rhyme or reason.
PARA
One of those instances is the sentence, "I want something to drink."
"I want" is translated easily enough: _Quiero_.
"Something" is translated easily enough: _algo._
"To drink" will cause a problem for the English speaker. In Spanish, you can't just use the infinitive "tomar." Drinking is actually the *purpose* of the something that you want, e.g., the reason you want something is to be able to drink it.
To indicate this, you use the purpose word "para." _Quiero algo para tomar._
The sentence then looks something like this, "I want something in order to drink (it)," or "I want something for the purpose of drinking."
TO DRINK
The word "beber" is what most dictionaries will give as the translation of "to drink." However, in actual practice, if you use the word "beber," you'll sound if you're talking schoolbook Spanish! The more commonly used word is "tomar," which also means to drink.
"Tomar" has two meanings: to drink and to take. You'll be able to tell which meaning it has by the context of the sentence. For example, you may hear someone tell you, _¡Vamos a tomar!_ This means, Let's _go drinking!_
SACAR UNA FOTO
Not only is there is more than one Spanish word for the English meaning, "to drink." There are also more than one Spanish word for "to take." Look up "take" in any Spanish-English dictionary and you'll see "tomar," "sacar," "agarrar," "coger" (be careful when using this word in Mexico!), and more.
There is only one appropriate Spanish word for "taking" a photo, and that is the word "sacar." "Sacar" also means to take out, as in "sacar algo del bolsillo" (to take something out of one's pocket) or "sacar dinero del banco" (to take out or withdraw money from the bank).
It may be easier for new Spanish learners just to memorize these useful phrases without trying to translate them directly into English! An essential part of becoming fluent is thinking in terms of the new language and avoiding any reference back to English.
Most schools DON'T teach Spanish this way, but that is the natural way a person would learn a language. It's what you would do if you moved to a Spanish-speaking country without knowing a word of the language and were forced to sink or swim. You'd begin to associate words and phrases with certain contexts or situations, and you'd even find yourself starting to use them without even knowing what exactly they mean in English!