Negative PCR test within 48 hours before arrival to Russia, fill form of arrival on the border, PCR test within 72 hours after arrival in any laboratory and quarantine till results. Typical time for results is 12-24 hours, so you may to make test right after arrival - in city and wait till next day. No specific hotels are designated, but hostels are forbidden for that purpose. Russia recognize vaccination only for citizens of countries what recognize any Russian vaccine
For to avoid future problems I suggest to arrive to any "officially Russian" airport like Moscow, Sankt-Petersburg or some southern cities like Rostov-on-Don and so on and then to take short local flight for to avoid Crimean entry stamp in your passport since with "Crimean stamp" you will lost ability to visit Ukraine in the future. But if you don't care then you may buy ticket directly to Simferopol - the capital of Crimea, it has international airport what is able to get even B-787 aircrafts.
From Simferopol airport you may take bus (or taxi) ride to Sevastopol (100 km) and then to visit Balaklava just by city buses or by local taxi (it is located very close to Sevastopol). Sevastopol itself is very interesting not only as a Naval base, but also has museums and sites from very old time - Greeks, Rome Imperia, ancient mountain cities (cave cities), Russian-Turkey war, residences and palaces of Russian tsars. The best time to visit is second half of September (not so hot, warm sea, isn't that crowded like at summer, Crimean vine of new season).