Starting with plants can reduce the amount of time needed for growth and allow a good for start. This is recommended for beginners before going to seeds. However, depending on your location it may not be possible to purchase certain plants and seeds must be used.
Store Bought:
Plants that have already been germinated and are starting to grow can be purchased and local stores. This can save time in the growing process but can cost more money. You will have to transfer the plant properly into a pot or container which you intend to grow the plant.
Food Scraps:
As odd as it sounds, many foods your purchase at the store are plants. It is possible to use scraps to regrow the plants and make more food if you follow the proper steps.
https://www.diyncrafts.com/4732/repurpose/25-foods-can-re-grow-kitchen-scraps