This is one of the first questions I get from anyone establishing a new business, and the honest answer is: it depends on what you're trying to protect and how you plan to grow.
Sole proprietor
The simplest setup — no separate filing, income flows straight to your personal return. The trade-off is personal liability. Your business and personal assets aren't legally separated.
LLC
Creates a legal separation between you and the business. It doesn't change your taxes by itself, but it protects your personal assets if the business runs into debt or legal trouble.
S-Corp
A tax election, not a business structure on its own — usually layered on top of an LLC once you're consistently profitable. It can reduce self-employment tax, but it comes with payroll requirements and more moving pieces.
I built and ran an international business right here — with clients spread across the globe — and the one constant is that the paperwork you choose at the start either saves you headaches later or creates them. This isn't a decision to make off a Google search — sit down with someone who can look at your specific numbers and goals before you file anything.