Well, you're looking for a career in film specifically, MANY people rock up to hundreds of film studios around the world each year (I mean literally within the 100,000s) around 50,000 of people have a moderate level of skill required, and only around 20,000 people have a massive amount of art skill, this includes technique, style and overall experience.
But what someone in the film industry is really looking for when it comes around to art (besides experience, certificates indicating level of knowledge and overall art skill) is how well you can create from scratch, something amazing and not copy anything else, so pretty much the ability to design from scratch something, you might be tasked with character art design or setting art (houses, backgrounds). Art is even required when working on live-action films, but I'm guessing what you're looking for is animation studios. It definitively is easier, however there are more people who study art who try to find a job in animation than there are for live-action.
Based on what I've seen so far; your art style is good, in saying this. it's nothing I haven't seen before, the style and technique aren't eye capturing, it doesn't put you aside from all the other hundreds and thousands of people who come around and ask for a job in the industry, I see you have a good technique on shading, many people find it really hard to shade properly, so many film companies do everything with computer rendering.
these drawings are very good for a 14 year old, and by the current skill I see, you have a massive opportunity to increase your art style to the point in which puts you off from the rest, what I'm trying to say is you've got a good art style and technique at a young age and this is a massive advantage for you if you're looking to get into film. most people don't get into a film industry until they have at least 2 years of experience + a advance diploma and over.
I would spend your time in the future, developing your own ideas and art styles, so instead of copying images like toothless from how to train your dragon, design your own dragon. Art in the film industry also requires you have an adept knowledge of the characteristics in your art, so when you make this dragon then be sure to explain things like what the dragon breathes, why the scales are that colour and what colours it changes to when certain lights hit the scales (this is just a simple example).