Company threatening to take disciplinary action against me

At my current job, my boss has been very controlling, micromanaging to different level and they didn't provide me with a work laptop. I agreed to install monitoring software for clock-in and clock-out, but when they asked me to install another program that invaded my privacy, I refused. Later, they sent me a lengthy handbook with a 1-year lock period clause that wasn't in my offer letter. When I questioned it, they said they would add a line saying as per the offer letter to make it okay, but a lawyer friend warned me that it might still be risky. Feeling uncomfortable and pressured, I decided to resign. After resigning, they removed the lock period clause and kept everything else and made me sign saying it was sent before resignation.After resigning, my boss continues to make things difficult for me over small issues, and they sent me a final warning email. They mentioned it was based on me sending weekly reports late a few times few months back. Please note this was before they gave me the handbook. This email threatens disciplinary action, including absconding from the company. The company also starts giving salary after 45 days of joining, adding to my worries. I'm seeking professional advice to understand my rights and what to do next.