Hi Bermuda58,
Are you Indian citizens? If so, you have the right to return to your home country. India has 'air bubble' agreements with 28 countries, including the UK and France, so you could fly to India via either London or Paris.
Alternatively, as Third Country Nationals, you can apply to extend your visa at the Spanish Embassy. Although this link refers to last year's lockdown, it may offer a precedent that could suggest the authorities might be responsive to an application for a visa extension (but just my personal interpretation):
http://www.exteriores.gob.es/Embajadas/NUEVADELHI/en/Noticias/Pages/Articulos/20200525_NOT01.aspx
However, if you've already overstayed the maximum 90 days, the authorities may be less than sympathetic. Whichever way you decide to proceed, best to do so without delay.
Good luck!
Kind regards,
Kim