The activation of Shopee logistics sea transportation usually requires the following steps:

1. **Understand the requirements**:

- First, you need to understand Shopee's requirements and regulations for sea transportation logistics. This includes understanding the supported routes, transportation time, fee structure, and any specific operating procedures.

2. **Register Shopee Store**:

- If you don't have a Shopee store yet, you need to register and open a store first.

3. **Logistics Settings**:

- In the Shopee store background, find the "Logistics" settings module. According to your store type and region, select the appropriate logistics service.

4. **Select Sea Transportation Service**:

- In the logistics service, find the options of sea transportation or international logistics, and select the appropriate service according to your needs.

5. **Submit Application**:

- Submit the application for sea transportation service according to the prompts, including filling in relevant information such as destination, type of goods, estimated delivery time, etc.

6. **Waiting for Review**:

- After submitting your application, Shopee will review your application. Once the review is passed, you will be able to start using the Ocean Shipping Service.

7. **Comply with the Rules**:

- When using the Ocean Shipping Service, make sure to comply with Shopee's platform rules and relevant laws and regulations.

Please note that the specific activation process may change due to updates or rule adjustments to the Shopee platform. If you encounter difficulties during the operation, you can check Shopee's official Help Center or contact customer service for help. At the same time, make sure to understand and prepare all the necessary information and documents when applying for the Ocean Shipping Service.