Departure card/embarkation card

Yes ---you may get a form when you get your boarding tickets.  If not just before you enter the departure gate for all gates there will be a long table with a scattering of forms but don't expect any pens.
You may want to read the Web of Corruption at the Tana airport. For arrivals and departures. 
Locals and residents rarely see this problem.  However when I arrived this time on Kenya airways I needed to pay for an extra bag to go onto domestic- cost was 50 Euros with receipt, and some one who worked at ticket check in said I could get my bag checked in for 40 euros no receipt.   I said no and he went off to sit with his friends two of whom were police who checked people through the line to go to domestic.
https://www.lonelyplanet.com/thorntree/ … he-airport