Technical SEO Courses (or courses in general)

Hi guys,

as part of my personal development goals, my founder/boss (Agency) is willing to sponsor a course for me to grow into my SEO consulting role inside the agency.

I was looking into the areas I kind of feel weaker in and with the most potential to benefit both my individual growth and business goals, as well.

Do you have any experience with Technical SEO Courses? Would you recommend any?
Any other "niche" courses work too.

Thanks in advance and have a great day!