Can chiral atoms have same substituents but with different orientations?
No, it is not an asymmetric centre. To test this, you can draw the two potential stereoisomers:



Note that isomers A and B are identical (by C2 rotation), so the nitrogen cannot be an asymmetric centre. If it were one, then these isomers would by definition be distinct.

The attached groups are identical, from the point of view of the nitrogen - both have (R) stereochemistry. If one were (R) and the other (S), the nitrogen would constitute a pseudoasymmetric centre - https://goldbook.iupac.org/html/P/P04921.html

Hope this helps.

Also, don't get confused about the difference between the nitrogen being a sterogenic centre, and the molecule as a whole being chiral. The molecule is chiral, since it is non-superimposable on its mirror image. Chirality is a molecular property, and although frequently people will refer to a particular atom in a molecule as "chiral", this is a misnomer. A better description of an atom with 4 different groups attached is "sterogenic". It is entirely possible to have a molecule containing stereogenic centres but the molecule is achiral (e.g. meso compounds).

The logic behind checking the plane and centre of symmetry is that planes and centres of symmetry are conserved on reflection in a mirror, so checking for these symmetry elements is a shortcut to checking whether a molecule satisfies the definition of chirality.