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In this study, we analyze the emission lines of different species present in118 Galactic field classical Be stars in the wavelength range of 3800 - 9000\AA. We re-estimated the extinction parameter (A$_V$) for our sample starsusing the newly available data from Gaia DR2 and suggest that it is importantto consider A$_V$ while measuring the Balmer decrement (i.e. $D_{34}$ and$D_{54}$) values in classical Be stars. Subsequently, we estimated the Balmerdecrement values for 105 program stars and found that $\approx$ 20\% of themshow $D_{34}$ $\geq$ 2.7, implying that their circumstellar disc are generallyoptically thick in nature. One program star, HD 60855 shows H$\alpha$ inabsorption -- indicative of discless phase. From our analysis, we found that inclassical Be stars, H$\alpha$ emission equivalent width values are mostly lowerthan 40 \AA, which agrees with that present in literature. Moreover, we noticedthat a threshold value of $\sim$ 10 \AA~of H$\alpha$ emission equivalent widthis necessary for Fe{\sc ii} emission to become visible. We also observed thatemission line equivalent widths of H$\alpha$, P14, Fe{\sc ii} 5169 and O{\sc i}8446 \AA~for our program stars tend to be more intense in earlier spectraltypes, peaking mostly near B1-B2. Furthermore, we explored various formationregions of Ca{\sc ii} emission lines around the circumstellar disc of classicalBe stars. We suggest the possibility that Ca{\sc ii} triplet emission canoriginate either in the circumbinary disc or from the cooler outer regions ofthe disc, which might not be isothermal in nature.

Optical spectroscopy of Galactic field Classical Be stars