All your uses of Bardic Inspiration will refresh after a long rest. The dice rolled will also increase, depending on the bard level of your character. Bard Level Die As mentioned, Bardic ...

That creature gains one Bardic Inspiration die, a d6. Once within the next ten minutes, the creature can roll the die and add the number rolled to one ability check, attack roll, or saving throw it ...

"When you cast a spell in this way, the willing creature also gains an amount of temporary hit points equal to the number rolled on the Bardic Inspiration die + your Charisma modifier (minimum of 1)." ...