how are players around 100-380 so good?

I've just looked at a bunch of your games.  Point to one single game where your opponent's knowledge or tactics or whatever seemed beyond his rating.

I don't think there is one.  I think you're getting a very fair pool of opponents.

Same thing as #2. 

Your opponents are... well... not very good.

If you are bad, you have no clue what is good.  Get better and you will see how bad your opponents are.

but then how do i go on massive losing streaks and keep getting mated so quickly and unexpectedly? im doing my best and it seems like that my opponents are just too good

you're experiencing what's commonly called a *skill issue*. ways to deal with this include: -coping -seething -malding -actually trying to learn from your games hope this helps!

im trying but its not that easy when my opponents are near-perfect when compared to me

You’re new. Chess skill isn’t developed in a weekend. Study more. Play slower. Learn those checkmate patterns. Skill comes in time with hard work.

There are some good resources listed at http://chessskill.blogspot.com/2021/11/learning-checkmate-or-teaching-it.html

Do puzzles, study your games, study grandmaster games. Keep a look out for checks, captures and threats. Good luck, you can do it! It just takes a very long time to learn chess.

i've been studying for months, yet still see no improvement in online games cause of how good my opponents are, im currently on a losing streak cause of the aforementioned reason

Try going along to a chess club, I'm sure your play will then improve greatly...

pretty sure that there are none nearby, is there anything else that i can do?

As Ziryab said, continue studying and playing. Chess is one of those activities you can't master in such a short amount of time. The skills needed is akin to learning to paint, sculpture or any other of the great arts. After 6 months you might have a basic grasp of things. Just keep going.

Figure out what your greatest weakness is, and focus on that part, then move to the next weakness, and you will develop a solid game, I can promise you that.

Yess

Months. That’s no time at all for a game with the depth and richness of chess.

Your opponents are beginners, albeit a little further along than you.

I learned the moves in 1968 and gained a slight grasp of the game in 1975. I won a weekend Swiss in 2016.

but a lot of people call players at this rating pretty much terrible, so why are they so good?

From your perspective they are good, most likely because you don't have enough experience.

You've been on chess.com for almost a year, and in all those months you took 0 lessons and solved 28 puzzles. "Studying for months", sure.

Just to be clear, playing 3-minute blitz with mostly random moves may be fun, but it ain't gonna make you better at chess.