|Does anybody knows why I don't have these options? Could it be a restriction from the Internet Service Provider?|
Potentially yes it could be. The simplest thing is for you to contact your ISP's support people and ask them. If they do restrict access to the router management interface they might grant you access if you ask them.
If they won't, you can always buy your own SOHO Router and connect theirs to it and then you would have access to that router's management interface.
If you're looking to do things like block websites or limit bandwidth, make sure you research before buying and find a router that does everything you want it to.
If you go that route (ie: add a router between your ISP's device and your users) you will want to click on my name above in this response and read my “how-to” guide titled, “Add a second router to your LAN”
You will want to use the scenario where you configure the second (downstream) router to be on a different subnet and interconnect the two routers "LAN port to WAN port"
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.