My favourite electronics distributor "AZ-delivery" has a blog where they posted a manual to create a "Solar Tracker" out of plywood. I asked the creator for a sketch so I can create STL for a 3D printer. He did me the favour and here we go.
Yes, there are already plenty of Solar Tracker designs on thingiverse, so what. Now it is one more.

Video on YT:
https://www.youtube.com/watch?v=tIO304yINBw

To find schematics and sourcecode for Arduino, just visit the (german) blog page:
https://www.az-delivery.de/blogs/azdelivery-blog-fur-arduino-und-raspberry-pi/solar-tracker-mit-schrittmotoren-und-oled-display

You can find a part list there, too.

My device is a bit different. I used a Wemos D1 R32 board, which is pin-compatible to UNO boards, but offers much more power, PINs, WLAN/Bluetooth and much more.
I used a breadboard instead of a perfboard. I hate working with perfboards, I'd rather drown the breadboard in hot glue. Only alternative for me is making a real PCB, which looks a bit too much work for this toy.

Code, 3D STL-Files, KiCad schematics, pictures and a video can be found on my GitHub:
https://github.com/Pontifex42/SolarTracker

These files are for free, but I please you to add a photo here if you make a copy. Thank you.

Artillery Sidewinder X2

Doesn't Matter

No

20%

The "cross" needs a brim. All others are printed without brim and without supports.
Depending on your printers calibration you may need to rasp the holes for the stepper motor axis by 0,1mm.
The four screws for the stepper motors should be flat head, but others may work as well.
Instead of screwing the limit switches, don't hesitate to use superglue.
For a microcontroller, I'd recommend Arduino Nano/Uno/Mega oder ESP8266/ESP32. Raspberry Pico may do as well.