Start small. Enthusiasm for gardening is great, but can rapidly dry up when the work mounts. Start with a #Small flower bed, say 25 square feet, which is room for around 20 to 30 plants with perhaps three types of Annuals and one or two Perennials. You can always increase you plantings as your experience grows.
If even a 25 square foot plot seems like too much, make a small border or do your first flower gardening in a container. Two or three plants sharing a fancy container can look stunning and give you a sample of what’s to come.