Hello friends;

I have a problem with DHCP.
I receive the Internet from the SXT radio, and DHCP is set to this SXT and I do not have the password and access to this SXT provided by the ISP.
I want to static IP clients.
So I put an RB750 router on my clients.
On my RB750, I launched DHCP server.
But again, the SXT radio receives DHCP clients.
How do I set DHCP on a RB750 router for clients?

Please help me.
Thanks.

I'd suggest to put your RB750 in router mode.
so the DHCP client on ether1 will pick up address from the SXT and DHCP server on Local bridge (include ether2 to ether5) will issue address to your own clients, with the DHCP server on the 750, you can set static DHCP entry as you wish.

Port1 is usually set for WAN by default on RB750.
If broadcast works I guess you put Port1 in Bridge (so now Bridge has eth1-eth5 ports) or you set your DHCP server with delayed response?
If you want to assign IP addresses yourself block DHCP traffic on ISP port and create DHCP server on your bridge.