Translation:What time in the morning do you drink tea?
"You guys" is slangy English and doesn't necessarily refer to men. It even works with entire groups of women. Down south we would say "Ya'll" to get the same meaning. In other areas of the country, you can spread that out to be "you all" or "all of you." But the generic "you" also works.
Yes, 早上 refers to the morning and 上午 to the time after morning but before noon. The time periods are not rigidly defined, just as the words "morning" and "afternoon" and "evening" are all general ideas in English, but the feeling I got was (roughly speaking) 早上 is 6 - 9 am and 上午 9 - 12. I'm sure others will offer different opinions.
If it helps, think of 午 as being noon. 上午 are the few hours leading up to noon, and 下午 are the few hours after noon.
What is the difference between using 上午 shàngwǔ - and - 早上 zǎoshang for 'Morning'. Earlier we used 早上, are were using 上午 because we are asking what time 几点????
Chinese divide the day up just a little differently than we do in the West. They have different references for early morning (say, before 6), morning, pre-noon, afternoon, etc. 早上 is morning, and depending upon the person (it's not like there's a formal definition) can be roughly from 6 - 9 am. 午 is the character for mid-day, so 上午 are the hours before noon, perhaps 9 - 12, and 下午 are the hours after noon. In most parts of Mainland China, 下午 can cover from noon all the way until night time 晚上, which for most people begins around 6 pm.
Your sentence is almost correct, but when asking a question in English you need to use "do." If you changed your sentence to, "at what time DO you all drink tea in the morning?" then it would be correct. (Although the initial "at" is optional, and to my ear it sounds more natural without. [I'm a NE USA native speaker.])
Your first sentence is improper English, but your second sentence is correct. The "do" is obligatory when asking a question in English. (except very colloquially, e.g. if I know that you drink tea but I just can't remember when, I might say: "you drink tea in the morning at what time?").