Pages's Blank word processing template has default tab stops set all across the page at half inch intervals.
You can add a tab stop at any marked increment on the Ruler simply by clicking at the point you want the stop to be placed. If you change your mind, you can drag the stop to a new position.
Double clicking on a tab stop you have set cycles the tab through the four available types:
Left: Tab key moves the insertion point to the tab stop. Text starts at the tab stop, and proceeds toward the right.
Right: Tab key moves the insertion point to the tab stop. Text ends at the tab stop, and added characters push the beginning to theleft.
Center: Tab key moves the insertion point to the tab stop. Text is centered at the tab stop, and added characters push the beginning to the left and end to the right to keep the text centered.
Decimal: Tab key moves the insertion point to the tab stop. Text ends at the tab stop, and proceeds toward the left. When a decimal point is placed in the text, it remains at the stop position, and text following the decimal extends to the riight.
Adding a tab stop to the ruler removes (or deactivates) all default tabs to the left of the newly set one. Tabs that have been set by the user remain. Any tab stop may be removed by dragging it off the ruler.
For First line indents, though, take advantage of the margin stop at the left end of the ruler. This margin stop has two parts:
The bottom part, a triangle, in the main part of the stop, It sets the position of the left margin for the whole paragraph,
The top part, a rctangle, is the First line indent. It sets the position of the beginning of the first line of every paragraph, as seen in the two paragraph sample (showing only the left three inches of a page) below:

With the first line indent set, there's no need to use the tab key at the beginning of a paragraph. Just press return to start a new paragraph; the first line will be automatically indented.
Regards,
Barry