brake /clutch fluid(s)

[Ed.Evangelista@domain.elided]

in cast iron 2 liter engines
i heard the same fluid goes into the brake refill canister
which also feeds the clutch fluid....???
is this correct ??
if so...what fluid(s) do i put into the brake refill canister??
dot #3,#4 brake fluid????....clutch fluid???
or does the brake fluid work for both??
what is the best brand(s) to use??

thanks
eddie

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