For the OGOship integration you need to generate API token from WebFlow.
Go to your project settings → Integrations → API Access
Click on "Generate API token".
Copy the generated token to your clipboard. This token will be used in the integration.
Go to myOGO "Edit merchant" page and select "Integrations". Click on "New integration" and select WebFlow from the list.
Paste your WebFlow API key (token) to the API token section.
Remember to save your changes. You can test your integration by pressing "Test" button.
Once you have integrated WebFlow you can synchronize your products with OGOship. Instructions are on product sync page.
Read also about setting up shipping methods.