Yes, similar triangles are congruent because in order to be congruent they must first be equal. Which in turn is the definition of a similar triangle. A triangle equal in angle measurements and/or side lengths. So, yes.
no theycan not
They are said to be similar but not congruent triangles.
Increasing the dimensions of the smaller of the similar triangles (if they are not already congruent) by a suitably chosen constant factor.
The term for two triangles that are congruent after a dilation is similar.