I mistook your Magnavox as having a tuner, sorry.
Apparently this is a very spartan model meant to be primarily used as a player. It has a "VCR" to the extent that every VCR can both play and record, but this unit is not particularly intended as a recorder.
The only recording input it has is via line, so if your satellite box does not have line outputs this Magnavox won't work for you. The connection needed would be satellite box line outputs to Magnavox line inputs, then Magnavox line outputs to TV line inputs. Assuming the sat box also has the channel 3/4 output, you could leave that connected directly to the TV so you could watch satellite straight thru on 3/4 when you don't need the VCR or DVD. Just switch the TV to line when you want to watch the Magnavox.
If your particular sat box *only* outputs over antenna wire to channel 3/4, you need to return this Magnavox and get a model that includes a tuner. Or, exchange your satellite box for one that has both line outs and channel 3/4 outs.
Ever since the digital broadcast switchover in 2008, the tuner parts in recorders have become much more expensive. Many Americans don't need the tuner, because they use a cable or satellite box with line outputs. "Tunerless" models like your Magnavox are designed for such people: they can save $50 or more by not getting the tuner. But it can be very confusing to people used to how old VCRs worked (all VCRs had tuners, all VCRs had both line outputs and channel 3/4 outputs). You need to match the recorder model inputs with your signal source: antenna, decoder box on 3/4, or decoder line outs. Unfortunately this isn't made clear by sites like Amazon or the kids who sell this stuff at Best Buy: we're left to figure it out for ourselves.