You came to the right place, you just need to give more information. First of all, you asked here in Cisco Digital Network Architecture. Is that correct? I mean, you do have DNAC and fabric switches in place? which version are you using?
Considering you have SDA already, your task is not something to worry. First, you need to create some identification for you IOT device, some Tag so that when someone plug them on de network, they will present themselves and the network will accept them the way they are and with the authentication they support. This is called SGT (Security Group Tag).. You need to create policy on DNAC telling with who those IOT device can communicate. Them, this policy will be automatic create on Cisco ISE by DNAC and ISE will apply it on the switch. This is call TrustSec Matrix.
Well, and this goes on and on. In order to help you, I am attaching an amazin material from cisco. Pay much attention on "SD – Access Architecture for IoT" part.
But, if you do not have SDA already and put the question here by mistake, then, your task is simples. In legacy network environment, you can connect IoT devices just like you plug a Phone. You may need to put them in one dedicate vlan.
Hope that helps.
