Controls for constraining transforms to operate along a single axis, or in a single plane, are on the default main toolbar.
The transform gizmo also provides a way to constrain transforms.
Restrict to X
Restrict to Y
Restrict to Z
Restrict to XY Plane
Restrict to YZ Plane
Restrict to ZX Plane
See also
Using Transforms
Using the Axis Constraints
Using the Transform Gizmo
