What would really help is reduce use of gas and oil, not bring them from elsewhere. No longer buying RUssian gas to get it from USA fracking, burning lots of gasoil to bring it across the atlantic, and having to build bigger infrastructure to regasify it onshore while methane lasts is wasteful.
Methane is finite, it leaks and causes more greenhouse effects than CO2, and gives CO2 when burnt. We should invest in renewable alternatives. And reduce consumption (less travel/commuting, better isolation, trains instead of highways, etc.). So that eventually we don't depend on Russia nor on the USA, Algeria, etc.
And the same for oil. A tanker just sank in Tunisia and if it leaks it'll be a disaster.. Fewer flights, more public transport, living without a car, fetching parcels from post-offices or depots instead of door to door deliveries...
If we just buy fossil fuels from elsewhere we won't be helping Ukraine. We'll buy from place X instead of Russia, so place X won't sell some amount to Y instead, to sell it to us. Then Y will buy it from Russia. Russia will get their money anyway, and we will still be dependent on someone. And if we go for biofuels, we'll end up starving. Ideally we should be able to produce oil from waste plastic and methane from CO2 for whatever uses we can't replace, but that seems too expensive today (in money and energy).