In order to be similar, they need to have the same angle measurements, but not the same side measurements. They need to be equiangular, but not equilateral. The lengths if their sides do need to be proportionate, though!
If their sides and angles are the same, they're congruent. In order to be congruent, they need to be exactly the same size and shape. They need to be equilateral AND equiangular.
This question was vague, but I hope this was the answer you were looking for. ❤️
