How can I use features with different length as input data for my machine learning?

Hej?

I am trying to create a machine learning for my buck converter in simulink. I am collecting 250 samples of data from the current of the inductor along with current and voltage of the capacitor and the output. My goal is to use these voltages and currents along with theire ripple as features in order to train the machine learning. However, the length of the voltages and currents are much bigger that theire ripples. My question is, do i need to have all my features to be of same length or is it not required. If they have be in the same length, How should i proceed?