I can plan this, but I need three inputs from you, and two parts of your request (the app, and "right now, permanently") change what I can do.
- Office IP addresses (required): each location's name and its IP address or range. Why: Google's internal traffic rule matches on IP.
- Existing data filters (required): name, type and state of any filters already in the property. Why: there is a limit of "up to 10 data filters per property".
- Web, app or both (required): you mentioned an app. Google's page says you "can't filter out internal traffic from app users", so this plan can only cover your website. For the app, I would need another approach, which is not in my sources.
About "right now, permanently": Google says once a filter is applied "the effect on the data is permanent". So I will not go straight to an active filter. The plan starts the filter in Testing, checks the matching data in Explore, and only then asks you to approve activation. Creating rules and filters, and activating them, each wait for your approval.