Creating a black panther statue

That's not really a 5V LED. Please provide a product link to what you call the 12V LEDs as well.
An LED's brightness is based on the current. So, decrease your series resistor to 270ohm for each LED to get just about the most brightness that they are rated for.

Do NOT use more than 5 LEDs with that board by itself. Adding more is cheap and easy-ish but you need to a MAX7219 if you want to use more than 5 LEDs.

Also, you are currently powering your MP3 player off of your board and that's not good. To address this we need to now how you plan on powering this after you are finished programming it. Do you plan on continuing to use the USB power?

Oh well, i um , went ahead and built this thing before i read this comment because i thought i had it sorted. I used a 68 ohm resistor as the data sheet suggested running off 5 volts with the 4.7 forward voltage and 15ma current. There a 5 on 5 pins. Im just trying to figure out how to time the leds to stay on for a min or two after the mp3 track is played. Also whats the issue with running the mp3 from the board. It will be plugged into the usb most of the time

This is the datasheet from the product that you linked. I do not see where it recommend using a 68ohm resistor.

Either your math is wrong or I am misunderstanding. You are running each LED off their own pin? Each with a 68ohm resistor? That means each can draw 5V / 68ohm or 73.6mA which is too much for the pin. That's why I recommended a 270ohm resistor as it provides 18.6mA which is safe for the pins and 5 together will not overload the port of pins.

Your MP3 player has an amplifier on it that draws too much current from the board. It's advisable to power it independently of the board and connect a signal ground to the board.

What will it be connected to for the rest of the time, if not USB?

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i used this online calculator to get the resistance. As far as powering it, as its a present for my step son i assume it will be plugged into usb or just used as a display.

Please link the online calculator.
Please link the datasheet.
Please answer these questions:

If these are yes, then your math is wrong and you will damage the chip at best.

https://drive.google.com/drive/folders/1-BLqrkjgZmuWxgC-QlhY9MzI5FoTdruF

LED Resistor Calculator This is the calculator i used, and the google link of the data sheet and the project.

So if i power the mp3 and the nano from a regulated power supply found in breadboard kits, it should be fine?

Breadboard kits generally do not contain a regulated power supply.

They may contain a "breadboard power supply" module which is moderately useless. :face_with_raised_eyebrow:

Don't you mean (5V - 4.7V)/68 ? The LED voltage drop prevents the full applied voltage from being applied to the resistor.

But, 4.7V sounds unbelievably high. Yeah, the data sheet says 3.7V. That produces a current of about 20mA. That falsely assumes zero ohms in the MOSFET driver.

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Well it looks and sounds cool, if the leds fail after xmas, so be it. Just need to work out the milis function so the leds turn off after a min or two.

The concern is not just about the LEDs. You can damage the Arduino I/O ports. But it seems like you're actually not overloading the LEDs.

You're correct of course. I've been distracted. I should step back until I can get my head back in the game.
Thanks for fixing my math.