I've got two questions regarding the Mikrotik Server.

1. I set IP Binding for my Wifi Router. 192.168.1.2 as WAN. My pc connect to this WiFi Router and get the IP address 192.168.100.100

Below is my rule in firewall filter:
/ip firewall filter add chain=forward src-address=192.168.1.2 dst-address=192.168.1.30-192.168.1.200 action=drop

However, I could still access to 192.168.1.30-192.168.1.200 network from my laptop. (my laptop connect with WiFi 192.168.1.2)

2. My Mikrotik Server provides hotspot to the users. After logging in, all those users should not be able to access my 192.168.1.30-192.168.1.200 network. How could I do that to restrict the access of the logged in hotspot users?

Traffic on the same network doesn't go through a router, those nodes talk directly. You cannot block that on the router.

Unless they're wireless clients, in which case you need to turn off default forwarding on the wireless interface.

thanks, but how to disable in the wireless router?

I also want to disable the connection between my LAN with the Wifi hotspot users.

Then what you should really do is create a virtual AP so you can run the hotspot on a completely separate network, or just put a different IP network on the radio if you don't need it for the LAN. Then you can use the IP firewall to regulate traffic between the two networks because they will be different networks like they should be, instead of being on the same broadcast domain.