I took classes, so I'd recommend you take a Korean class. If that isn't possible, I've heard good things about this site: http://talktomeinkorean.com/

I used the TTMIK course at Memrise as main source of learning for a very long time. In addition to that I have had some lessons with teachers on this site.

You could try these below: https://www.youtube.com/channel/UCBpRNdkIp4LSUCgXOcp1NSQ https://yourkoreanguide.com/ While many other sites/materials try to bombard you with vocabularies resulting in many awkward expressions, Jeremy explains the fundamental structures which will make many things easier to understand in the long run. And he's so spot on. Strongly recommended.

Thanks!

howtostudykorean.com , talktomeinkorean.com , memrise.com (for vocabulary)