yes for a target scope .
Have it drilled and tapped by a good gunsmith.
nope
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
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 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.
The typical Marlin 39A does not have a scope. They are drilled and tapped that one can be added.
Check the scope mount makers web sites or call Remington.
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.
The receiver will need to be drilled and tapped for a mount. See a gunsmith.
I seem to recall that may be the same gun as a Stevens 416. Most of those guns did not have drilled and tapped recievers. They did have drilled and tapped barrels for old style target scopes. You will probably do better to take it to a competent gunsmith and have him drill and tap it to fit a currently available scope base.