Prerequisites to learning Passive and Active Filter Design
There are math intensive ways, or matrix methods or easy online tools.  But you ought to understand how they work.

Filters are generally defined by ;


center fo , -3dB BW, bandpass ripple , Band reject fBR,   Attenuation @ fBR  which affects order N
then band shape offers many choices : Butterworth Q=0.7, Chebychev with X dB BP ripple., Gaussian, Bessel (lowest Q,), Linear Phase,  Raised Cosine ( null ISI) etc.
even order , odd order, BPF + Notch , Tolerance and Sensitivity analysis (better with low Q)
Filters are a result of complex impedance attenuation ratios
matched impedance for RLC filters 
Active includes ; Gyrators ,   Transimpedance,  Sallen-Keys and Multi-feedback Active (positive FB and negative FB gain )


There are a bunch of free web filter design tools, that get a design quickly that may required impedances to be raised or transposed  or balanced.
  (TI (reg. email), Falstad.com > Circuits > Pass,Active ...)

For Falstad> Options> show phase... adjust slider options.