you just cannot use word-by-word translation (so Google has no chances)
Google doesn't always use the WFW.
It uses the so called "Translation Memory" concept when certain pieces of text have their own fixed translations like "take a ride" = "прокатиться", not "взять поездку". But the database supposed to be maintained by the users isn't progressing very much and it does use the word-for-word translation for the rest so you're right, it awesomely sucks

Hello! I'm really bad at this, but I want to (start) speaking already. I've been learning to speak Russian since January, I know around 100-something words, (which is) not so much. I (didn't know the word for could so I went withwould) probably say more, but on different subjects.
be bad at sth = не разбираться в чём-то / плохо разбираться в чём-то (я очень плохо в этом разбираюсь)
start doing = начать / начинать делать что-то (но я хочу уже начать разговаривать)
around (in this meaning) = примерно, около
100-something - we don't say it exactly the same way, we say "something like..."
... я знаю что-то типа ста слов ... (informal. there are tons of other ways to say this: я знаю около сотни слов, я знаю примерно сотню слов, etc.)
I spelled the hundred just to let you know how the russian equivalents of the around-thing manage the subject (hundred), each in its own original way.
Also pay attention that the word "сотня" is the same as "сто" in a way like "a dozen" is the same as "twelve".
I would say and I could say can be the same in Russian: Я бы мог сказать. Also "I would say" can be "я бы сказал", which can mean either "I would say" or "I would have said" depending on the context.