The short answer would be to consult with the Russian consulate nearby. But be prepared — the process will surely be tough and time-consuming.
The list of documents required for the application might vary depending on the category you fall into, but could include an application form, a copy of a residence permit, a translated passport, photos, and a birth certificate. According to the 2019 amendments, some categories of foreign applicants will no longer be required to renounce their existing citizenship, pass the Russian language test, or provide proof of their financial income. Alexander Inoyadov, lawyer at BMS Law Firm, notes that these privileges only apply to compatriots participating in the resettlement program, migrants from Ukraine, and citizens of Afghanistan, Iraq, Yemen and Syria who were born in RSFSR and previously had Soviet citizenship.