How to organize DHCP with two subnets on UbuntuServer?

Question

DHCP

Good day. A question has come up. Started working in an organization, no DHCP and DNS. It is necessary to raise DHCP for one subnet with the number of clients +/- 300 clients (not counting the server equipment) and the second for distribution via WIFI to +/- 100 clients. What is the best way to do this?
The server acts as a gateway to the "outside world" while on board UbuntuServer.
Thanks in advance.

Answer 1

Well, there are many ways.
1. Set up multiple DHCP zones on the Ubuntu server. But then you have to reserve all clients in one of the networks. Those. the principle is this: we reserve certain IPs for all MACs on the subnet. This zone we will issue only to them. The second zone will give out to the rest. But the solution is crooked, like an earthworm broken in several places.
2. We set up the first zone for ordinary clients, we set up the second one on a router with Wi-Fi. There is an obvious problem with NAT here, but it can be avoided if NAT is disabled and you play around with the VLAN and/or subnet mask settings correctly.
3. If Wi-Fi "distributes" the same server (for example, a router / point is connected directly to the server, via a separate interface), you can configure the distribution of zones for specific server interfaces.

Answer 2

Good. I assumed to configure 2 zones on DHCP. In zone A, plug clients with computers and equipment, and in zone B, cut the router. Moreover, distribute DHCP on the router in zone B, and register it with statics in zone B. Crutches, but it can work out.
From this there are 3 more questions:
1) Will zone A and B see each other with access to the outside?
2) How to create a similar bridge on Ubuntu?
3) What are the best addresses to use? 10 or still 192 can be dispensed with?
The roof is already riding on the amount of work. I just can't stand in the "kaleya" and remember network technologies.
Thanks in advance for your replies.