Some business opportunities you can start are only open to you in your own country, others allow you to sponsor long distance and build an international team. Often it is helpful as a new business owner to start local and learn your business close to home. Then when you get more confident and have built a track record with proven systems supporting your business you can branch out and go global.
One of the main things to look for is the age of the company you are joining, Often new start ups under 5 years old are risky, so I would avoid anything being sold as "ground floor opportunity". it's too early for most people to be confident you're investing in something that will last.
Another critical element for a local, national or international business opportunity is a proven business building SYSTEM. Systems are what automate your business growth. Systems are what allow you to be sponsoring new customers and representatives worldwide even when you are asleep in your time zone.
A third key element is a sponsor who has a way to teach new members how to get started on a fast and proven track. A sound initial 30-day plan would be something I would look for.
Because some businesses do change over time and may, on occasion even fail, you also want to be looking for a system that is building MULTIPLE sources of income. Personally, I like to have 5 or 6 sources all integrated to make the most of my advertising investment. One of the affiliate programs I work with has members in over 130 countries including India, Brazil, China, Mexico, the Philippines as well as the United Kingdom and of course the USA. Good hunting and let me know if I can help you!