Containers are easy for the beginner. Think of it as a very small complete garden that is mobile.
Start with cold tolerant plants and then weed out some of them and add more heat loving plants.
Understand your light conditions for the plants you choose. Full sun is 5 hours or more. Partial sun is 3-5 hours and shade is 3 hours or less.
Contrast is important in container gardening. Start with a plant that you love and combine it with plants with contrasting texture, color or form. Pair a fine-textured plant with a heavy-leafed plant, yellow-greens with red-violets, etc…….