How does "拥有" differ from "有" in usage or meaning?

"Have" is a broad concept, refers to a place has something, a behavior, etc., can also be said to exist, can be public or private. "Possession" is a relatively small concept. It refers to something owned, dominant, and inviolable. Have a lot of money, land, etc

“拥有”的宾语必须是双音节名词，并且是大量的东西。

eg: 他拥有土地。/他拥有丰富的资源。（✅）

eg:他拥有一百块钱。（❎）

1.有：他 有  很多钱。has       /  拥有：他拥有很多财富。possess       “有”多用与口语中， “拥有” 是书面语

2. 有：那里 有   一棵树。 there be 表示存在，“拥有”没有这个意思

有 has more meanings.

拥有,

• possess;
• have;
• own (a great deal of land, population, property, etc.)

有,

• have; 他有钱。
• there is, exist; 桌子上有一本书。
• indicating estimation or comparison; 他有我高吗？
• used to indicate ample amount; 有经验
• ……

“拥有” in English means to possess, but “有‘’ just means to have,  when we just want to state the fact without any personal emotion, we use ”有”