You are warmly welcome @nyama. I also joined steemit and completed my achievement1 some days ago. And I am very excited I did. Blockchain is the future and it is a blessing to be introduced early. If you want to learn about blockchain you can read more about it from here Free Book on Blockchain Fundamentals
From what I have read so far, understanding blockchain Its not a hardcoded requirement to thrive on steemit but steemit thrives on blockchain and for me I believe it's better to know of the fundamentals of the platform and at least a little bit about its inner workings