I see there are ways to create, delete, read individual opportunities here: https://developer.salesforce.com/docs/api-explorer/sobject/Opportunity
How to get all opportunities owned by a salesforce account using their rest api?
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Sign up to join this communityI see there are ways to create, delete, read individual opportunities here: https://developer.salesforce.com/docs/api-explorer/sobject/Opportunity
How to get all opportunities owned by a salesforce account using their rest api?
Assuming you need to fetch all Opportunities associated to an Account, you can just use Query resource for this purpose.
In your case, your API call should look like:
https://yourinstance.salesforce.com/services/data/v43.0/query?q=select+name+from+opportunity+where+accountid='<the account id>'