• If you are back on your feet, you have returned to physical or financial health.
• back on your feet とは、肉体が健康な状態、あるいは財政が健全な状態に戻る、つまり、回復する、という意味です。

Explanation

1. (supervisor to employee in the hospital)a: How soon do you think you’ll be able to return to the office? We miss you there.b: The doctor thinks I should be back on my feet in another week or so.
2. a: How’s the business going? Back on your feet yet?b: We’re not just back on our feet. Business is positively booming!
3. I realize that the staff hasn’t had a pay raise in three years, but until we get the business back on its feet, a wage increase is simply out of the question.
4. The firm hired a high-priced CEO and hopes that he’ll be able to put them back on their feet again.