I have a question about manage items stock / outstock google ads I've tried to use Google Scripts - but it decision not matched for me, because page code site has often change by developers Google Ads API - is it decisions for my requirement? Someone use it for manage ads - for stop ads if items outstock?
Yes, this is a good use case for the Ads Api.
I'd recommend you start with the API quick start: https://developers.google.com/google-ads/api/docs/first-call/overview