there are three ways to turn push notifications off if you don't want them:
1. turn off notifications at the app level in iOS app settings for Feditext
2. in Feditext, go to Preferences → Push Notifications → turn off all of the notification types
3. in Feditext, go to Preferences → Push Notifications → set "Receive push notifications from:" to "No one"
2 and 3 are per-account settings, so keep that in mind if you use Feditext with multiple accounts.