Hey there @shiftrox 👋
.. basically, whenever you use an information from a source in the internet, than you are not using your own intellectual property, but the intellectual property of someone else .. whenever you do this without stating the source, you are plagiarizing .. only whatever information you get from your own brain is your own intellectual property ..
f.e.: .. if you write, "there are so many different species of bees out there" , then this is your own thought as you can state this without looking anywhere in the internet or in a book ... But if you state that "there are more than 16.000 different species of bees", than you got this number somewhere from the internet and have to source it properly .. everyone can know that there are "many" species, but an "exact information" is not as trivial and someone out there worked for getting this number.
another example: if you write that "the oak tree in front of me is super huge, approximately 20 meters" , than this is from your own mind. But if you write that the oak tree is a huge tree and that "there are species of the oak tree that were measured up to 23 meter" , than you refer to a exact number, 23 meters, that someone reported somewhere else. thus you have to quote it.
there is only one exception, and this is common knowledge ... f.e.: if you write that "there are many different classes of animals, such as fish, birds, reptiles and mammals" ... , than this is considered as common knowledge. Of course someone investigated this once, but this is an information that everyone knows and that has not be looked up in the internet, a book or elsewhere, and information you took from your own brain. Even knowing that a tree is an oak tree can be considered common knowledge
.. depending on what you write and to whom you write, the us of other peoples intellectual property can have serious consequences ^^ .. If you do this for example in scientific publications, like a bachelor, master or doctoral thesis, they university can even take away your academic title even years after you gained it ;)
But just to be sure: whenever you look up a site to get whatever information you need to write in you own text, then just copy&paste the link at the end of your post, even if it is just a simple number or other fact .. This is actually done in a few seconds
I hope this was helpful. For any more questions you can always leave me a message ^^
Best wishes 😉