Seeking help on false police complaint and fir filed by friend

Hi all, I need advice on a dispute that turned into a police complaint. About 2–3 years ago, my friend and I had normal arguments on WhatsApp/Telegram, just typical insults like calling each other fake, nothing serious or threatening. Recently, I found out more about his fakery and sent him a moderately insulting message, no threats, nothing serious. After that, I blocked him. Then he started OTP bombing and call/SMS spamming me, so I unblocked him to call him out over Whatsapp, then blocked him again. He tried to contact and argue but I ignored all messages/calls. Frustrated, he filed a complaint against me in Bangalore under harassment, verbal abuse, and defamation. Before also I'd seen him threaten to file fake police complaints against others when upset. He sarcastically sent me the complaint number and said he plans to go to the police station tomorrow to talk to them. I live in Pune, and I want to know: 1) How will FIR and investigation work across state lines? 2) Can police refuse to register FIR in such minor disputes? 3) Should I get a lawyer now? 4) How strong is a complaint based on a single moderate insulting message after years, especially when he also harassed me with OTP bombing? 5) Will this affect my career if the FIR closes without charges? 6) Affordable legal help options in Pune? 7) Do I need to travel to Bangalore because of this? Thanks in advance!