all you will need is the public IP address that you want to use for your webserver, private address of the webserver if you want to dedicate a single IP to be used for the webserver.
A NAT instance needs to be configured so all traffic to the specific public ip will be forwarded to the given private ip
eg
static (inside, outside) 209.165.201.12 10.1.1.3 netmask 255.255.255.255
you then may want to put an access-list on so only specific ports will be allowed through to the webserver
eg
access-list acl_out permit tcp any host 209.165.201.12 eq www
then apply the access-list
access-group acl_out in interface outside