Multiple ISP to Multiple SSID

I am very very beginner here, need some help and advices.

My place got :
3 different ISP with different modem each
10 Edimax ceiling AP ( able to create multiple SSID )
1 Unmanaged POE Switch ( connect to all the AP )
1 Mikrotik CCR1009-7G-1C-1S+

The goal is :
To create 3 SSID which each one of it connect to the different ISP.

I have no idea how to do it, need some help and advice.
Note : I don’t mind buying new Mikrotik wireless and use all of those AP as repeater only, but maybe I can Find better solutions here