NVDA/Screen reader HTML Table accessiblity

I am working on a web application that should be fully accessible through keyboard and/or screen readers.

In this application I have some data tables. The information I could find about tables is that its html should be semantically correct, it must contain caption and tr/th and scope and aria-row/colcount... But what I can't find is how this should be accessed.

(1) Should I add a roving tabindex so, tab would focus on the first cell and other cell/rows be accessible through arrows, and another tab key would move focus to next focusable element on the screen, leaving the table?

(2.1) If my table has focusable elements inside (but only for one column per row) the focus move to the element, but somehow I should be able to read the content of each cell, right? In this case, should it be accessible to arrows or only through specific keys (ctrl+alt+->, for example)?

(2) I tried installing NVDA and pressing "T" to read the table, but even though I have all the aria attributes in a semantically correct html, it simply ignores the table; Same thing happened in other websites...

(3) I've added caption and labelledby but since the table is not a focusable element, NVDA doesn't really read it.