yes for a target scope .
Have it drilled and tapped by a good gunsmith.
That is hole that has been drilled, then had a thread 'tapped' into it so you can insert a machine screw or bolt.
no it has a 3/8 dovetail rail
Shafts are drilled deep into the ground and the gas is tapped and brought to the surface.
That gun was made by Marlin for Sears, and those holes are not factory. Someone has drilled and tapped it for (probably) a Weaver side-mount base.
The spindle/caliper bracket is threaded.
The typical Marlin 39A does not have a scope. They are drilled and tapped that one can be added.
The Woodsmaster 750 is Remington's gas-operated, semi-automatic action, center-fire rifle. It comes fitted with either a walnut or synthetic stock, a detachable magazine, 18.5" or 22" barrel with iron sights (the receiver is drilled and tapped for scope mount). It is available in the following calibers: .243 Winchester, .270 Winchester, .308 Winchester, .30-06 Springfield and .35 Whelen.
if it did not come with the provision to mount a scope on it you can take it to a gunsmith and have it drilled and tapped for one.
Check the scope mount makers web sites or call Remington.
The receiver will need to be drilled and tapped for a mount. See a gunsmith.