Twenty-two journal prompts for letting go — of grudges, habits, old stories, and the outcomes you cannot control.

"Let it go" is advice that assumes you know how. Most people do not, because letting go is not a decision you make once — it is a specific thing you keep noticing and putting down, usually the same thing, for a while.
These twenty-two-four prompts break it into pieces small enough to work with: which grudge, which habit, which story, which outcome. Naming the particular thing is most of the work.
Vague weight is impossible to set down. "I need to let go of the past" cannot be acted on; "I am still rereading an email from March" can. The prompts that ask which and what are doing the useful job.
Expect to write the same answer more than once. Letting go is repetitive by nature, and finding the same name on the page in three consecutive months is information, not failure.

1. “What can I let go of that's been holding me back?”

2. “What past mistakes can I release in the name of self-forgiveness?”

3. “In what areas of my life can I release control and follow my intuition?”

4. “In which areas can I release the need for an outcome and simply enjoy the process?”

5. “What limiting beliefs am I ready to release?”

6. “How can I begin to let go?”

7. “What uncontrollable situations can I exhale and let go of?”

8. “What bad habits can I release, to make space for a new version of me?”

9. “Which negative relationships can I release to make space for positive people and healthy connections?”

10. “What past resentments or grudges am I ready to release?”

11. “What bad habits from my past can I release today?”

12. “Which bits of self-criticism am I ready to release?”

13. “Which false stories do I need to release?”

14. “What unproductive habits can I release and replace with better ones?”

15. “What can I let go of in my life, to make room for the better things I desire?”

16. “What past trauma or doubts need to be released, for my own happiness?”

17. “Which comparisons can I let go of, to focus on my unique journey?”

18. “What regrets can I let go of as I embrace living in the present?”

19. “How can I make space for peace and calmness while letting go of my worries and anxieties?”

20. “How can I let go of my doubts and fears?”

21. “Which unfounded worries or anxieties can I release?”

22. “What grudges or resentments can I release, for my own peace of mind?”
By noticing it and choosing not to continue it, repeatedly, rather than by deciding once. In practice that means catching the rehearsal — the imagined argument, the reread message — and stopping it a little earlier each time.
No. You can stop carrying something without deciding it was acceptable. Conflating the two is why a lot of people stay stuck: they are waiting to feel forgiving before they are allowed to put it down.
Because unfinished feelings resurface until they are processed, and because habits are grooves. Recurrence is normal; the useful measure is how long it holds you rather than whether it appears.
For everyday resentments and habits, often yes. For trauma or grief, journalling supports the work but is not the whole of it — that is a reasonable point to involve a therapist.