I did not specifically find a tutorial on how to connect/integrate google sheets to kintone, but I have found a website that is recommended by kintone called Zapier.
Zapier is an extension for you to try out and to connect the apps and to automate workflows.
Please take a look.
1. You choose a trigger - pick an event in an app that starts your Zap
2. Choose an action - An action pulls the data from your other app(s) to complete a task on your behalf.
3. Each time your Zap runs, it automatically and securely sends information from one app to another.
Also, I have attached a link for a page where you can sign up using your Google account and check to see different types of triggers & actions it has and as well as a step by step instruction on how google sheets and kintone integration works.
Google Sheets + Kintone Integrations:
Hopefully, this answers your question.