How much RAM should be allocated to a virtual machine?

[Demow]

I set up Ubuntu 24.04 on Vbox with 6 GB RAM and 2 processors allocated. It may not provide the exact experience as normal, but it seems to have a slight lag. Is this normal?
Processor: 12th Gen Intel(R) Core(tm) i5-1235u, 1300 MHz, 10 cores, 12 logical processors.
32.0 GB (usable: 31.8 GB)
64-bit.