Welcome to the forum!
I would recommend looking at LEDFx paired with WLED which will give you a GUI for controlling addressable LEDs with little to no coding required.
In the past for wearable LED projects I’ve used Battery Holder - 2x18650 (wire leads) and a voltage buck set to 5V as a means of portable power. The batteries with the voltage regulator end up being around 75mm x 40mm x 30mm give or take depending on where you put the regulator and weighs about 100g, you would also need an ESP device to run it, something like our FireBeetle Board ESP32-E (Arduino Compatible) will work, although any ESP32-WROOM will work, ESP32-C3, ESP32-S2 and ESP32-S3 may also work but certain features may not be available.
