Travel to Spain full vaccinated with a Russian vaccine

For Spanish authorities, non-WHO vaccines do not confer "vaccinated" status.

BUT, if you have the complete series of Sputnik-V (which IIRC are two doses), then you will only need one dose of a WHO vaccine (which include all of the EMA vaccines). The EU Digital COVID Certificate (DCC) will show that you have 1/1 doses of the EMA/WHO vaccine (you could also get one of those if you had been infected with COVID, since then only a single dose is administered as part of the regular prescription).

Be aware that the acceptance of vaccines that are recognized by the WHO but not the EMA (e.g. CoronaVac) may vary from EU country to country. We had issues with people who got the DCC at Spain but then had trouble in Italy because they only did recognize (at that time) EMA vaccines.

Source: I work as a programmer at a public healthcare organization and I have been tasked with the program that issues our DCC.

As I said in the comment I posted, you'll need to get two doses of EMA-approved or WHO-approved vaccine (or, if you lack your booster, get at least the booster as an EMA/WHO-approved vaccine) as stated by the official travel site

Sputnik V is in neither WHO's list (read the Status of assessment column for the list) nor EMA's list so you are actually considered unvaccinated in most EU countries

Exception can happen, but for touristic reasons they'll basically never happen