Focus on making connections between your background and the skills listed in the job description. It's not necessary to go through your resume step by step. Instead, choose three or four different aspects of your background and elaborate on each with two to three sentences. It usually makes the most sense to approach this question from a chronological or reverse chronological perspective (don't jump all over the place).

"My first position in SEO marketing taught me the most. I was mentored by the senior marketing manager, who taught me a lot of the fundamentals of SEO and how to apply them. I also realized how closely SEO Specialists work with other people on the marketing team. After that, I worked for a smaller company where I was the only person responsible for SEO. To be honest, I was a bit underprepared for that role, but I learned so much out of necessity, including doing my own SEO audits and even writing a few blog articles to boost keyword optimization. The company I work for now has given me a lot of opportunities to learn, and I've become strong in my analytical skills and ability to identify potential issues before they become a problem."