What is H1b renewal process


I have an expired H1b (expired in Sept 2018)
I was in USA on H1b for 3 years (Oct 2013 to Jan 2017) and had to move back to India due to personal issues.
I want to go back again to US. Can my H1b be renewed under cap-exempt category if applied this year, 2021?
In case my current employer doesn’t file it…What would be the best way to find employer who can transfer and renew it from India?