1. 今天早上没有阳光，所有空气都有多云 

今天早上没有阳光，多云。or 今天早上没有阳光，天上很多云 or 天上云很厚。（空气 is usually modified by 好／不好／清新 fresh／浑浊 polluted；“多云” is a type of weather condition, similar expressions from the same category include 晴天 sunny、阴天 cloudy、多云 partly cloudy， something between 晴天 and 阴天、下雨，and etc.)

只看到灰蒙蒙（hui1 meng2 meng2）的一片。（空气 is acceptable，灰蒙蒙的空气 is fine, but 灰蒙蒙一片 is commonly used when you want to describe an unclear view.)

3. 无论天气是不好，我们还是去超市

无论天气好不好，我们都会去超市。

即使天气不好，我们还是去了超市。

Can you tell the difference between the two? 无论 cannot be used for a past event. However, when giving a general description of a routine (e.g. 无论天气好不好，这家饭店都开门。）or one's intention (无论他喜欢不喜欢我，我都会给他写email。）

无论 MUST be followed by a “x不x” structure or “A还是B" (A and B are usually the opposite): 无论天气好不好 or 无论晴天还是下雨

4. 而且我很喜欢下雨让环境变得安静下来

This is ok. But 而且我很喜欢下雨让周围安静下来 sounds more natural. The suffix "~下来“ already indicates the change/action, so the "变得" in your original sentence becomes unnecessary.

5. 所以我们有很多空前(空间）看所有产品

This does not sound very Chinese. Do you mean that you can take your time to explore the products without being rushed? In that case, 所以我们可以慢慢地逛（超市）。You can also use 悠闲 （you1xian2）to replace 慢慢. 

6. 刚才我休息一下吃优各

Chinese people usually say 酸奶（suan1 nai3），not sure if Taiwanese say 优格 though.

7. 不过这样优各没有味道，并味道有点酸 

Use 并且 instead of 并 here. They are very different. 并 is always followed by a VERB (or sometimes, an adjective), BUT NOT a sentence. In another word, 并 cannot connect two sentences as 并且 does. In your sentence above, it consists of two sentences. The first subject is "yoghurt" while the second subject is "taste". Therefore, you have to use 并且，not 并. See more examples below:

A. 他每天自学汉语并通过了hsk4级考试。B. 他每天自学汉语，并且他通过了hsk 级考试。

A. 他把女朋友介绍给大家，并说她是世界上最漂亮的女孩。B. 他把女朋友介绍给大家，并且，他说他的女朋友是世界上最好看的女孩。

The 并 in all the sentences A can be replaced by 并且 as well while 并且 in B cannot be replaced by 并.

8. 不好吃，所以吃完后我吃一块巧克力，好吃唷！

Just want to remind you that the 唷 sounds very cute/friendly and usually is considered as something feminine. Nothing bad about that, just make sure it is the tone that you want to express. "哦“ usually has the same function as 唷, which might be slightly less feminine. "啊” can express a strong emotion too when you exclaim at something but it does not sound too cute. “他妈妈做的晚饭真好吃啊！” Young people will use 特 or 超 or 超级 to modify the extent of the adjective，such as 巧克力超好吃！！！