2 Red LEGO compatible bricks I'm not sure where I got these 2 pieces from, and I'm wondering what are they, and which brand they belong to.

They are LEGO-compatible, but definitely not genuine LEGO.

There are no identifying marks.

Here are some photos:
Those look like Best-lock bricks.

The red looks to be lighter and more-transparent, like Best-lock bricks do compared to Lego.



The studs have no markings.



The 1/2/5 looks like the ones found in Best-lock sets, like this one.