Do I need to carry all my luggage on my trek or have the facilities of safe locker? - Day

Whether you are able to carry all your luggage or have the availability of a safe locker depends on the trek undertaken and the provider selected. Most of the guided treks make available porters to carry your luggage so that you can carry only a daypack with necessary items in them. A few accommodations may also have safe lockers where you can store your valuables.

It would be a good idea to discuss this with your trekking company so that you understand their policies and particular arrangements, which exist in the case of your trek. If you have a particular trek in mind, then I can try to help you find more detailed information.