What Chinese lesson (Category of words) should I be studying?
You have difficulties identifying words and recognizing patterns.

eg:


香山公园风景美丽。 vs
香山 ／ 公园 ／ 风景 ／ 美丽。


The landscape at Xiangshan Park is beautiful.

公园 is a very common noun. You should be able to identify it. And look at the sentence rhythm: 2 / 2 / 2 / 2.


骑自行车: If you don't know this expression, you already have a hint in the question. The expression appears twice, and 自行车 alone, without 骑, appears in the table of 8 words. Reading a problem carefully is always a good idea.


So there's a hint: 自行车 is a single, 3-character, word. So you have a structure like this: 骑+自行车. If that doesn't announce Verb+Noun I don't know what does. You might not know what a 骑兵 is, but since you didn't circle 马 I assume you know what it means. 骑 has the horse radical, so it's not too wild to imagine it has to do with riding . Especially with a xx车 vehicle... Context is always important.

What you need to do is:


Improve your vocabulary. Read more. Spend time with a dictionary. Paper dictionaries are usually more useful for learning. If you spend time looking up characters by hand, you'll get more familiar with their radicals and stroke numbers, stroke orders. And reading through a paper dictionary is far more interesting than online.
Focus. Don't panic. As you have discovered, just scanning words in an app doesn't work. Identify patterns. I've mentioned 骑自行车, but #14 for instance is just a question of writing down the exact same word as in the original text: 香山公园风景........[美丽]. How hard can that be?


Good luck.

Addendum

Look up the vocabulary requirements of HSK 1 &amp; 2 to start. Make sure you know all the words in there.