Wet the potato with warm water, then use your hand or a vegetable scrub brush to clean the potato. Be sure to get into any dips or rough spots to remove any stuck-on dirt. If you’re peeling the potatoes, you might skip this step. However, it’s helpful to start with a clean skin so that you don’t accidentally transfer dirt from the skin onto the edible part of the potato. Red and gold potatoes are easier to freeze than russet potatoes because they will blanch well whole, even with their skin. If you’d prefer to chop them up so they’ll be ready to cook later, use a sharp knife to cut them into cubes or slices. If you prefer, it’s okay to peel your red and gold potatoes before you freeze them. Place the pot of water on the stove, then turn the heat to high. Watch for bubbles rising from the bottom to the top, which means the water is boiling. You should see consistent bubbling on top of the water when it’s boiling. Potatoes that are about 1.5 inches (3.8 cm) or smaller are considered small, and potatoes that are larger than this are considered large. However, potatoes that have been cut should be treated as small potatoes. Set a timer so you can keep track of the cooking time. Use a plastic bag with a zipper or a plastic food storage container. Leave about .5 inches (1.3 cm) of space inside the container. Label the container with the contents and date they were frozen. Then, put the container in your freezer.  It’s a good idea to pre-portion your potatoes so that you’ll have enough for 1 meal in each bag. You can store your potatoes in the freezer for about 12 months. Be sure to write the date on the container so you can keep track of how long they've been in the freezer.

TL;DR in Vietnamese:
Cọ rửa khoai tây để loại bỏ đất cát. Để nguyên củ khoai tây đỏ hoặc vàng, hoặc cắt nhỏ nếu thích. Đun sôi một nồi nước trên lửa lớn. Chần khoai tây trong 3-5 phút nếu là củ nhỏ, và 8-10 phút nếu là củ to. Cho khoai tây vào hộp đậy kín và đông lạnh.