How do I change the port of the web interface?
I mean something like 192.168.1.1:8080 instead the default 192.168.1.1?
Or filter the IP or mac addresses that can use the web interface?
I recommend the basic “Protect your router” at the bottom of the firewall filter section of the documentation. This is minimum for me:
/ip firewall filter
add chain=input action=drop connection-state=invalid
add chain=input action=accept connection-state=established
add chain=input action=accept protocol=icmp
add chain=input action=accept protocol=udp
add chain=input action=accept src-address=xxx.xxx.xxx.xxx/xx
add chain=input action=drop
Change the x’s to the IP/netmask of the computers you want to access this box from. You can enter more than one set of IPs if you wish, just enter them above the last rule. Insure all is correct and working before adding that last rule, or it will lock you out of your own box. Then a null modem cable is best for regaining control.
The order is important. If you enter them in the wrong order, you can rearrange them with the move command:
move 3 1
moves the rule from line 3 to line 1, and the rules in between are moved down.
This set of rules also stops those pesky hack attempts at your other ports, like telnet and ssh.
Thank you for trying to help…
I understand the filter rules, but I’ll stay “simple” for a while.
Firewall filtering maybe later when I get more pro. 
I found this…
IP > Service …
and then filter my IP only.
Something like…
“edit www address” and
“edit www port” for the port.
Thank you!
not ‘edit’.
more like:
/ip service [enter]
print [enter]
set 2 port=8081 [enter]
read here:
http://www.mikrotik.com/testdocs/ros/3.0/qos/service.php
Just a warning…If you do not use the firewall filter rules, insure your password is really long and has caps and numbers in it, or the box may not be under your control very long. 
When I was new, I did the same, and used a short password (6 characters, no caps or numbers). I lost control of that box in less than an hour.
ADD: I just checked a box I set up the other day. I setup the IP/mask and routes, DNS, DHCP, then the firewall. I can do this pretty fast too! By the time I had all the filter rules in, I had 4 hack attempts from 2 different IPs in my log already.