National fund purchases can be made on online financial platforms, securities companies and third-party financial platforms.

1. Online financial platform: Many online financial platforms provide services for purchasing American funds, including Fidelity and Pioneer.

2. Securities companies: Many securities companies also provide purchasing services for American funds, and choose securities companies with trust to buy.

3. Third-party financial platform: Third-party financial platforms also provide purchasing services for American funds. These platforms all have certain risks, so you need to be careful when choosing them.