First things first
To start off, I'm going to try to address some of your thoughts that look like you might have bought into some myths. It's important to get those out of the way first and foremost, not to criticize but rather so we're on the same page.
I've always wanted to try lifting but given my body type and height, I've always been scared of bulking.
Lifting weights doesn't suddenly bulk you up. We (guys), even with the help of our testosterone, have to jump through insane hoops hoping to bulk up. Let one thing be clear; step one of bulking is you gotta want it. The next eleven steps include copious amounts of hard work, and a strict diet.
There will never come a day where you wake up, go to the mirror and think "dammit, I'm a bodybuilder, which is what I wanted to avoid".
If you're worried about putting on size, direct that worry towards your food first.
I'm an endomorph
This is just pedantry perhaps, but the whole ectomorph/mesomorph/endomorph phrasing used to belong primarily to a way of categorizing the human physique in a way that didn't turn out to be as helpful or scientifically sound as it seemed in the 1950s.
When you describe yourself as endomorph here, we tend to understand it quite simply as "I tend to put on weight if I don't watch my eating habits", so the phrasing has a certain value to it. But if you happen to talk to the right person with the right knowledge, they might draw conclusions that go beyond that. Maybe things you didn't intend.
Further reading on Wikipedia.
Yet I recently read an article saying that "You get bigger before you get smaller" and the science behind how your body adapts and responds to exercise.
I haven't read that article, but the title sounds like an oversimplification, or outright crap. Benefit of the doubt and all, let's just assume the former. I see no reason to conclude that someone who is looking to lose weight should have to gain weight first.
Also is the myth about getting bigger before getting leaner true? Has anyone ever experienced it? I'm especially scared for my quads and legs as they bulk up very very easily.
It's common practice, but it's not carved in stone. A lot of us find it easier to gain muscle and fat at the same time, then diet down the fat afterwards, for a net gain of mostly muscle.
If you're looking to avoid putting on size on your legs, that doesn't mean you should avoid training them. Mostly it just means you should keep your eating in check, but also there are ways of training legs that result in functional strength rather than volume.
What do you need to do?
Form, shape , exercise type? And the lingo? cutting? bulking? splits? recomp? Ngl im getting pretty overwhelmed. Do I use dumbells? Do I do squats? deadlifts? How do I build a routine for myself? How much weight should I begin with?
Ok, here's the good news. The first thing you need to do is let someone else make all those decisions for you. A rookie should never make their own program. There are tons of programs already out there, written by people in the know.
A rookie making their own program is going to
- neglect muscle groups because they don't know where half of them are
- develop muscular imbalances by working out some muscle groups more than others
- perform exercises with poor form, increasing the risk of injury
Really, the only thing you need to do is some basic research. There are thousands of programs out there, and I can't really pick one for you because it's impossible for me to say which one is best for you. So what you need to do is google around for some programs. They should have a description of some sort stating who the program is meant for, and what kinds of results you can expect.
Find a handful of programs that match your wavelength, and try each one for a few months. I know that sounds like a long time, but that's because changing one's physique takes time.
Most importantly, figure out if a program is fun or boring. The program you look forward to doing week after week is going to be far more effective than the boring program that makes you skip sessions.
