By the time the Soviets had been invaded by their Nazi Ally— Lend Lease had long been ended (in re: its application was to the UK prior to US entry into the War).
No- the Soviets milked US military support, banked, stole and copied it. On their own they could not have defeated Nazi Germany at the time of their piss poor reaction to Barbarossa. The German miscalculation was having a two front war— because Soviets had little they needed, aside from the obvious oil resources Germany did not have.
The Soviets went out of their way at Yalta to cash in on the bonanza— and stupid FDR and stupid Truman accommodated them. No surprise when one looks at major Soviet spies in the US cabinet (including one, Alger Hiss, who wrote the UN Charter documents! The Soviet UN working in conjunction to steer US “interests” even then).
Read this book, probably gives the best information I have ever read on the German-Soviet Conflict and it change your perception of the Eastern Front War.