How does one do a spec-ad sir?

@Spenser Sakurai Thank you sir. To be frank, I’ve hit a bit of a crossroads. I’ve been a videographer for eight years, but over the last two, my passion has shifted toward stylized documentaries and commercials. I want to focus on the cinematography side of the industry. However, I’m struggling to break in because my current network consists almost entirely of event videographers. This leads to a cycle of job offers for shop launches and events. I’ve tried pitching to agencies and producers, but I often hesitate when they ask for my portfolio. I feel my current work doesn't meet cinematographer or DP standards, and that lack of confidence usually leads to me ghosting them. I’m ready to move on from my videography career, but I’m not sure how to effectively start my journey as a DP.