You demonstrate results from your past and current work. You build trust through word of mouth and reviews (amongst other things). Just be able to display results.

Start talking to businesses about how you've helped people. The main difference is that now instead of talking to an individual about how it can help them, you need to think of how this helps a business - businesses operate for one reason only, to make a profit. So how will your services create value for the business? Once you can succinctly explain this, start reaching out to businesses and open a line of discussion. Try to determine a good target market, though, as there are nearly an infinite number of businesses out there - who can you help the most and how?

You need a good idea that is properly executed, and then get really lucky... you are using the top 0.0001% of entrepreneurs as examples. Forget the money, you need to learn how to grow a business, and at 17 I'm sure you have no clue. Start networking, get a job, learn how business works in the first place before worrying about how to become the next Bill Gates (or just do what he did and steal someone else's software code to peddle as your own...).

I would also encourage you to look for better role models - yeah, these guys are rich, but by most accounts are horrible human beings. I can point you to a lot of successful entrepreneurs who are also good people. They might not be billionaires, but they are still starting and selling businesses worth millions.

Then reach out to TV producers, I don't think you'll find them hanging out here...

IMDb Pro, Mandy, and personal networking are your best bets. Also worth mentioning, I don't know ANY media companies BUYING reality TV shows... the entire reason these things exist is because they are incredibly cheap and easy (relatively speaking) to slap together, and bring in big bucks for the networks. These types of programs are almost always packaged in-house. Not to mention, there is no shortage of ideas, and it sounds like all you have to pitch is an idea (everyone has an idea in entertainment, everyone has a script.... these are the cliches that constantly ring true).

So not to end this answer on a downer, I'd buy an IMDb Pro subscription, if you're serious about this, and start pitching producers that have worked on similar projects, but... realistically, I wouldn't expect to get very far.

Higher value projects that producers are more open to hearing about from outsiders are original narrative feature scripts, or original series (you'd need to have at least a pilot and bible written out, and potentially a full season).

- I worked in film/TV for several years in L.A. and Seattle

By talking to them. Welcome to the world of sales! I would like to ask why you started a business with no clue how to find customers, though, as it seems like you've skipped some steps. You need to start reaching out to businesses if you're going to find clients. If you're just bootstrapping, I would start calling and emailing just about anyone under the sun, and trying to network with others in your market. You need to gain a little traction first before you can better consider how to scale.

Identifying your target customer is step one, though, and really should have been done before you even started the business, to ensure there is demand for what you're providing. You also need to have a defined value proposition, especially as you are entering a highly saturated marketplace filled with experts commanding very high salaries, and LOTS of people scrambling for any business they can get.

I'm also curious as to why you started an agency versus freelancing...

I answered a similar question asked just after yours... an MVP, or some sort of market validation, would be the first step. No point in building it if no one will use it (unless for fun).

Create an MVP, that's why startups do this all the time. An MVP doesn't have to be a piece of software or technology, it doesn't have to be a functional site. Your goal is to test for market value, essentially, and find the people that would see value in this. You've already identified a target prospect in your question - small businesses that design and sell manufactured products. Ask yourself, how does your idea help them, and what sort of ROI can they expect.

There are a lot of resources online these days for getting contact information for such businesses. You can simply reach out and ask the business owner if it's something they would be interested in (and collect other useful feedback on your idea).

Otherwise I would suggest finding appropriate groups online, network locally, and basically just talk about your idea with as many people in the target market as possible. You can do all of this for little to no money, it's just your time, but this would be the simplest way I can think of to validate your idea. From there, if there is identified demand, you can look at building out an MVP and starting to get a user base you can grow.

You are entering a space with a few VERY big names that people go to without even thinking much about it (Agoda is partnered and integrated across many channels, for example, as well as being highly optimized for Google).

Talking business strategy would be a separate matter, but to answer your question as someone who has traveled EXTENSIVELY and lived in many different countries, the two biggest factors for me is price (many of these large competitors of yours have partnership deals with properties around the world, and so can offer discounts - when I worked in hospitality years ago, there were always locked in discounts for anyone who booked through Orbitz, for example), and thoroughness (searching across as many potential properties as possible).

You also have to consider that Airbnb is a HUGE competitor these days (they like to position themselves as a partner in the hospitality space, but let's face it, speaking for myself, I stopped using hotels since Airbnb came around many years ago).