The correct order of basicity is

Aliphatic amines are more basic than aromatic amines because the lone pair in aromatic amines is delocalized into the benzene ring via resonance.

$$p$$-methoxyaniline: The methoxy group ($$-OCH_3$$) exert a strong $$+M$$ (Mesomeric) effect. This highly increases basicity relative to aniline.

Aniline: It has no additional substituents. The lone pair is delocalized into the ring, making it less basic than aliphatic amines but more basic than those with withdrawing groups.

$$p$$-nitroaniline: The nitro group ($$-NO_2$$) is a powerful $$-M$$ and $$-I$$ group. This highly decreases basicity.

Thus, the increasing order of basicity is $$p\text{-nitroaniline} < \text{Aniline} < p\text{-methoxyaniline} < CH_3NH_2$$