Hello Kartik,
The images did not come along in your post, but the issue that you are having is most likely related to the padding and/or margins of the tables or sections. To fix the issue, right click > table properties for all related pieces and check the padding and margins. If anything is auto, set to 0 or the desired amount.
The second piece requires some test publishing to get the layout you want because things will render differently from preview to the browser, and from browser to browser. We recommend publishing often to tweak the UI to the layout and alignment that you want.
Another thing to try would be a container table. This would be a 1 cell table with padding and margins set to 0, and left aligned to line all of your tables up.
Hope that helps!
Bre