Good night, How are you? I am needing your help to see if the project I have in mind is possible or not. My idea is to make an RFID reader that can read a card and be able to manipulate the information on it using a 4x4 membrane keypad. I plan to use Arduino UNO, the RC522 and a 16x2 lcd display. I know that the explanation is very basic and rudimentary but broadly speaking that is my idea. Sorry for my English.
Yes that is a perfectly possible thing to do.
Yes is it possible.
Brilliant! If it's not too much trouble, could you help me out on how to get started with this? It should be noted that I am new to this beautiful world of Arduino 
this can be your head start
Take a look at the last two examples
Well to start with you need to wire up the Arduino to the RFID reader. Almost everything you will read about doing this with an Arduino outside this forum is wrong.
But first you have to say what sort of Arduino are you using? Is it a 5V one or a 3V3 one, because this is vital to know before I can tell you how to wire it up correctly.
Thank you very much man! It's a 5v Arduino!
You will find it best to be exact with details on this list. That's a nice start, it probably reduces the number of possibilities by a factor of 2 or 3, but most Arduino products have a product name, and in addition it would be useful to know if you're talking about a clone, or genuine Arduino product.
@IoT_hobbyist
I managed to see enough of this first link on my iPad so I could scroll down and glimpse the diagram of the Arduino connected to the RFID reader.
This is the same sort of amateurish rubbish you see all over the internet. It will eventually destroy the RFID reader.
In fact that first link just seems to be a copy of this website:-
RFID and Arduino Uno
Without all the cookies bit on the front end. It is also not the way to connect a Uno to an RFID reader.
The problem is that the data signals from the Arduino are 5V signals and with the RFID reader being a 3V3 device it is receiving signals greater that its supply voltage. This is a very bad thing and puts a lot of strain on the static protection diodes in the RFID chip.
So to prevent this from happening you have to cut down the signals from the Arduino Uno to the RFID reader. The signals from the RFID reader can go directly to the Uno. Theoretically these signals are not enough to drive the Uno but in practice it seems to work but it does no harm to try. But you really need some sort of 3V3 to 5V level shifter here. Don't use a bidirectional one designed for I2C as these are too slow to use with SPI unless you slow the SPI clock down a bit in software.
So here is the correct way to wire up a Uno to an RFID reader. Or in fact any 3V3 SPI device to a 5V processor.
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I've removed the post with all the links to rubbish information packed out with advertising. Also the replies to that post in order to keep things clean.
@IoT_hobbyist ,
I know you are trying to be helpful but please be careful when posting links to external sites. I looked at one of the sites you linked to and it was full of advertising. @Grumpy_Mike also identified that the information on those sites is very poor quality, and I guarantee Mike really knows what he's talking about.
Thanks
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Thanks Perry. Just to see what I could come up with to support what I was saying I did a forum search for :-
RFID stopped working
And there were lots. Not all of them down to the wiring some were when servos or relays were used.
But enough said they stopped working and had to reset the Arduino to get it going. This is known as "latch up" and is a well known thing. This normally comes about when sending a signal into an un-powered device, but can also happen if you exceed the input voltage on a pin like the bad diagrams show. This might not be a permanent condition but it is on the way to being so.
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Thank @PerryBebbington and @Grumpy_Mike.
Firstly, I will pay attention for next replies. I thought it is useful.
Secondly, I will investigate the articles, do some test again to fix any error if found.
Thank your guys again!
Remember I said that testing one piece of hardware is not going to tell you much about anything.
Thank you for your valuable comments.
I temporary added a wiring diagram with voltage divider as below:
Any suggestions are welcome!
I see you have decided to change the resistors. This will probably work but the lower values will give you faster edges.
Well done 
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