Hyperledger Fabric Samples having examples for Bookmarks.

Please find the sample code below. Entire Chaincode can be found here

func (t *SimpleChaincode) QueryAssetsWithPagination(ctx contractapi.TransactionContextInterface, queryString string, pageSize int, bookmark string) (*PaginatedQueryResult, error) {

	return getQueryResultForQueryStringWithPagination(ctx, queryString, int32(pageSize), bookmark)
}

// getQueryResultForQueryStringWithPagination executes the passed in query string with
// pagination info. The result set is built and returned as a byte array containing the JSON results.
func getQueryResultForQueryStringWithPagination(ctx contractapi.TransactionContextInterface, queryString string, pageSize int32, bookmark string) (*PaginatedQueryResult, error) {

	resultsIterator, responseMetadata, err := ctx.GetStub().GetQueryResultWithPagination(queryString, pageSize, bookmark)
	if err != nil {
		return nil, err
	}
	defer resultsIterator.Close()

	assets, err := constructQueryResponseFromIterator(resultsIterator)
	if err != nil {
		return nil, err
	}

	return &PaginatedQueryResult{
		Records:             assets,
		FetchedRecordsCount: responseMetadata.FetchedRecordsCount,
		Bookmark:            responseMetadata.Bookmark,
	}, nil
}