Hey there!
Your answer is no.
I'll give an example to prove this wrong for you.
We have one rectangle with the dimensions of 2 x 6 units and another rectangle with dimentions of 4 x 4 units.
The perimiter of the first one is 16 because the four sides added up is 16: 2 + 2 + 6 + 6 = 16
The perimiter of the second is also 16. 4 + 4 + 4 + 4 = 16
So, they both have the same perimeter, but they are not congruent because their sides are different lengths.
Hope this helps!