You can use the Align panel to align or space selected objects horizontally or vertically to the selection, margins, page, or spread.
To align objects, click the button for the type of alignment you want.
To distribute objects, click the button for the type of distribution you want. For example, if you click the Distribute Left Edges button when Align To Selection is turned on, InDesign makes sure that there is an equal amount of space from left edge to left edge of each selected object.
To set the space between objects, either center to center or edge to matching edge, select Use Spacing under Distribute Objects, and then type the amount of space you want to apply. Click a button to distribute the selected objects along their horizontal or vertical axes.
To set the space between objects (facing edge to facing edge), under Distribute Spacing, select Use Spacing and type the amount of space you want between the objects. (If Distribute Spacing is not visible, choose Show Options in the Align Panel menu.) Then, click the Distribute Spacing button to distribute the objects either along their horizontal or vertical axes.
When you use spacing with vertical distribution, selected objects are spaced from top to bottom, starting with the top-most object. When you use spacing with horizontal distribution, selected objects are spaced from left to right, starting from the left-most object.