Recommend me microcontroller for this project

[Gaber Mohamed Boraey]

Hello
I need Pic for this project concept

3 buttons for control 6 led strips, and 2 buttons for brightness control

I need the project fit in 20*13 mm pcb

 

[Aussie Susan]

You are going to need a bigger PCB if you want it to hold the MCU, 5 buttons, the ancillary components (supply bypass capacitors etc.) and (presumably) connectors for the power supply/battery and LED strips.
Are the LED strips similar to the WS2812B LEDs?
You will need a minimum of 5 GPIO pins for the switches, 6 for the LED strips (2 each). That means you will need an MCU with at leat 16 pins.
What level of embedded programming experience do you have? What languages?
Do you want to use an MCU with internal pull-up or pull-down resistors (smaller footprint but only some MCUs have this) or are you happy to have these as external components (certainly will not fit on a small board with everything else)
You may need a small amount of RAM but my guess is that quite a few K of Flash memory will be needed.
I suggest that you work out the schematic first and then use the Microchip product selection page to find a suitable MCU.
(To be honest, going by the way the question is asked, I suspect that you may be in over your head at this stage. Perhaps get some experience with PIC programming, especially how to develop embedded apps, how to interface with the switches [there are traps such as contact bounce to consider] and also how to control the LED strips [there are libraries available but they may require quite a bit of flash memory space]. Start slowly and step by step build your experience.)
Susan