TD-DFT output from Gaussion can be read by GaussView (http://gaussian.com/uvvisplot/). You can also us Chemissian (http://www.chemissian.com/) to simulate it. Gaussian calculate oscillator strength where you need to add a Gaussian band shape to get the spectra. You can play with the band width so that the calculated spectra closely resembles your experimental spectra. The plot is against absorption coefficient not absorbance. Absorbance depends on the concentration.

It depends what you exactly want. If you want to see the 0-0 transitions you can use TD-DFT as implemented in Gaussian.

If you want to predict the vibronic spectra follow the protocol of V. Barone, J. Bloino, M. Biczysko, http://www.fc.up.pt/pessoas/mjramos/EMTCCM-2016/EMTCCM_MalgorzataBiczysko_3.pdf . Please note that this is very computationally expensive.

Thank you for your recommendations