Looks like you are trying to upload a .zip
file. Appstore accepts .ipa
file created using the Xcode archiver.
Just a suggestion: Before submitting app archive, validate it using Xcode. Follow this tutorial to know how to validate archive using Xcode. Fix issue that come up during validation, then submit.
In case you have confusion or are new to app store submission process you can read through this Apple guide: App Distribution Guide
Hope this helps!