You might be a bit confused there if you think that 1) BRICS is only Russia or 2) that they only produce oil. The first 4 countries are there specifically because they together command the biggest markets and populations in the world except for the USA (I still don’t understand why South Africa is there, but they’re nice too), and the block is quickly expanding as a broad anti-imperial financial coalition. That means natural resources like oil, minerals (gallium, lithium, uranium), wood, but agricultural produce like the soy used in livestock feed around the world, and even high tech products such as cars, computer parts and weapons.
In the specific case of Venezuela, if they need food, natural resources, high tech equipment or even investment from the BRICS’s New Development Bank, they’ll have much better luck from within BRICS than alone, without having to worry about invasions or sanctions from the “blocks full of cronies” of the EU, USA or broader NATO. It is great news if you care about Venezolanos having better lives from now on.