Connect ad accounts from your project's Settings (or straight from the Paid Ads tab). The flow: pick the platform, approve access in the platform's own login popup, then choose which ad account to bind to this project.
Currently connectable: Meta Ads, TikTok Ads, and Snapchat Ads. Google Ads and Apple Search Ads are coming soon.
One connected credential can be reused across your projects: you pick the ad-account binding per project.
Once connected, the Paid Ads tab lights up with your spend, impressions, clicks, conversions, and per-platform breakdowns, and approved campaign creative can be pushed directly into the account.