To split the dataset of images into train_data, train_labels and test_data, test_labels with separated folders, below given steps might help you in getting started:
Define the split ratio.
Shuffle the image files to ensure random distribution.
%imageFiles is a folder with all the images and labels.
numImages = length(imageFiles);
randomIndices = randperm(numImages);
Split the dataset
trainCount = round(trainRatio * numImages)
Copy the image and label to the destination directory