This gist contains a GoogleSheet implementation for Swift

GoogleSheet.swift

import Foundation

struct GoogleSheet {

    /// Fetch CSV parsed data from a certain sheet.
    ///
    /// - Parameters:
    ///   - id: The unique sheet ID.
    ///   - name: The name of the sheet to parse, by default the first.
    static func csvData(
        fromSheet id: String,
        name: String = ""
    ) async throws -> [[String]] {
        let url = "https://docs.google.com/spreadsheets/d/\(id)/gviz/tq?tqx=out:csv&sheet=\(name)"

        guard let url = URL(string: url) else {
            throw NSError(domain: "Invalid URL", code: 0, userInfo: nil)
        }

        let data = try await URLSession.shared.data(from: url).0
        let string = String(data: data, encoding: .utf8)
        guard let string else {
            throw NSError(domain: "Unable to convert data to string", code: 0, userInfo: nil)
        }
        let rows = string.components(separatedBy: "\n")
        let parsedData = rows.map { $0.components(separatedBy: ",") }
        return parsedData
    }
}