SEO Course recommendations?

Hi all, I am an online marketer with 1.5 years of experience in marketing, mainly with content marketing, SEO and social media marketing.

I’ve got a study budget at my current job allowing me to do a course on anything I want basically. Since I want to keep evolving in SEO, I wanted to do a course on this topic.

However, most SEO courses are basics which are things I am already 100% familiar with/have already applied in the field.

I was looking at a minidegree from CXL (opinions?) but not sure what else I could be looking at that are advanced SEO.

So I come to you, Reddit: what courses / websites do you recommend?

(Dutch courses also highly welcome!)