1000 accounts is a lot, and it’s tough to manage alone. You’ll probably need automation tools with that many. I don’t use automation myself, and I only manage about 100 accounts across different platforms. From what I’ve seen, creating IG with Gmail isn’t as trusted as using a phone number. Even better is creating IG through Facebook, make or buy FB accounts first, then log in to IG. For antidetect + proxies, I use Hidemyacc. The built-in proxies there work fine for X and scraping, but for IG I’d get separate proxies. Residential IPv4 is the most trusted, or mobile proxies if possible.