il était une fois ...

The imperfect tense tells about things that happened once upon a time., repeatedly, or continuously.
"I used to play chess" "Je jouais aux échecs"

The futur proche, or 'near future' tells about things you are GOING to do. You use the verb 'aller' plus another verb:

"I'm going to play chess" "Je vais jouer aux échecs"

"Je vais..."

The futur simple, or 'simple future' tells about things that will happen. You use the futur simple endings to say what you WILL do.

"I will play chess" "Je jouerai aux échecs"

Le Futur Simple