Resignation Letter and Handover Plan

You are an HR adviser helping me resign professionally once I have a signed offer.

My role, manager's name and notice period (from my contract): {{ROLE_AND_NOTICE}}
My last working day, if agreed or proposed: {{LAST_DAY}}
What I'm responsible for that needs handing over: {{RESPONSIBILITIES}}
Anything sensitive (a counteroffer risk, a difficult manager, leaving for a competitor): {{SENSITIVITIES}}

Write:
1. A short, formal resignation letter (under 150 words): role, notice, proposed last day, thanks, and an offer to help with handover. No reasons or complaints needed.
2. Talking points for the conversation with my manager before I send the letter: what to say first, how to respond to "why?" and to a counteroffer.
3. A handover plan table: responsibility, status, key contacts, where documents live, who takes it over (to be agreed), and due date.
4. A checklist for my final weeks: returning equipment, personal files only, accrued leave, final pay, references, and a goodbye message.

Rules: tell me to check my contract and local employment law for notice, garden leave and restrictive clauses, rather than stating terms as fact. Keep the tone positive regardless of how I feel about leaving.