To support that type of bandwidth you will generally be using microwave (> 2 GHz) or higher frequencies. Reliable communications will be limited to line ifof sight situations.
This type of application is well beyond the homebrew capabilities of most hobbyists. The good news is commercial world has a wide range of cost effective products available for these types of applications. The frequencies, power levels, antenna gains, and licensing requirements are generally country specific. To get started, you may wish to look at a company like Ubiquity. There are many such companies on the market and most offer excellent guides for properly and legally deploying their products.