You can use a public dedicated IP address or a IP address of you local network. If you use a public IP you should be able to connect normally with the IP to your server, if you select a internal IP address you have to route the traffic with iptables to the internal IP address.
Does this answer your question?
Yes but,if i use public dedicated IP (same ip have dedicated server ) and start connect in putty,I will be AUTOMATIC connected to a dedicated server or not?
You can't use the same IP for two machines (for your host and for a VPS). You need an own dedicated IP address for it. The only solution I know is to give the OpenVZ VM an internal IP address and example forward the port 22 with iptables to the VM in the background.
I don't know any tutorial about this topic, sorry. Maybe you can take a look in the Proxmox wiki.
For example:
Give the OpenVZ machine the internal IP address 192.168.1.2 and redirect the port 1122 from the host to port 22 on the virtual machine with iptables: iptables -t nat -A PREROUTING -d IP_FROM_THE_HOSTSYSTEM -p tcp --dport 1122 -j DNAT --to 192.168.1.2:22