Yes, you can use the card immediately once you receive it.

The problem that you are reading arise because the person was not so smart and to post the actual image of the card online for the whole world to see for reasons that I could not fantom at all. 
So you decide to use the card online, whether you cover the number or not is not important because no website will ask for the physical card image and you should scram if any website that does that. Only the card number (and some other details) is required.

Don't call yourself a noob coz only a noob would be really that dumb enough to post the image of their physical card online. Take some effort to understand what was the problem was all about and don't scare yourself just because something happen. Scaring yourself silly is another noob syndrome.

If it is really a problem then don't you think no one will use credit card at all in restaurants ? The newspapers will pick it up and BNM will response to this public and serious complaint.

What you think is a problem or what your friends tell you is likely to be a myth. The guys in here range between 1 year to more than 10 years of using credit cards experience and I'm sure 99.5% of them don't have this problem. If you feel un-secure then you may cover the numbers but please be aware that some cashiers are trained to rejects cards which are fishy. They may tolerate covering the CVV but to cover the numbers ??? Try it yourself and let us know of their response. Please don't waste our time asking us to answer your silly questions which you are too afraid to risk it yourself.

Actually if worried so much, then should just use cash.

Chill la, just don't worry so much, everything will be alright.

Just a precaution, do not reveal the cvc code to anyone, and try not to let your card out of your view when you pass it to the cashier/waiter to avoid the card being cloned.

Some here, including myself, has tried to cover the cvc code using tape but sometime the cashier/waiter's hand itchy will strip it out