How to open multiple EEG data in a folder and rename the data in index sequence?

clc; close all;clearvars;
addpath('C:\Users\xxx\Desktop\xxx\mne-matlab-master\matlab');

folder = 'C:\Users\xxx\Desktop\xxx\Seizures';
filePattern = fullfile(folder,'*,raw.fif');
myFiles = dir(filePattern);

for k = 1 : length(myFiles)
    fullFileName = fullfile(myFiles(k).folder, myFiles(k).name);
    raw = fiff_setup_read_raw(title);
    Fs = raw.info.sfreq;
    [data,times] = fiff_read_raw_segment(raw);
end