I am still very new to vector and I wanted to make something similar to this image.
I want to make it as circular shape. The only idea I got is to manually draw it point by point. Any better techniques?
using Adobe Illustrator.
That is a "round-rect" with a simple brush stroke applied to the stroke... could be done in any vector editor which supports brushes - could be Illustrator, or Affinity Designer, or InkScape.
In all three of those vector art apps, there are ellipse tools; in almost all cases with pre-canned shape tools, when you hold shift as you pull out, this will constrain the aspect ratio to 1:1. So if you choose a rectangle tool and pull holding shift, you get a square; if you choose an ellipse tool and pull holding shift, you get a circle.
Then apply a brush you like, and you should be all set.
Hope that helps.