From BDM in a Fintech to IB

Hi all, I'm actually working as a Business Development Exec for a rising fintech (series A level) based in London. I would like to switch and start working in IB (M&A preferably) - where should I start applying and for what kind of position (analyst or intern)?

I graduated in sept 23 with a bachelors in Economics (2:1) and I have a year and a half of work experience (internship that lead to a full time job) - can I still apply for off-cycle internships too? 

Thanks guys!