For your first practice you need three things: a racket, balls and a court. That is all.
A soft tennis racket is light, so it is easy to handle, and your wrist and elbow take less strain. If you have played tennis, you will feel the difference immediately — it is lighter.
Start with training balls. They are cheaper, and for learning they behave the same as tournament ones. A dozen is enough at the beginning.
Soft tennis is played on a regular tennis court. If you have access to a court or a sports hall, you are all set.
You will learn the rules in a few minutes. Points count up to four, and a match is played to winning the majority of 7 or 9 games. The rest you will pick up as you play.