Suzuki 2 Strokes

I recently purchased a 1977 GT380, the service manual does not mention removal of the front tire. Can you simply remove the axle holder screws and slide the tire out, disc and all?

No. Take the two clamps off the base of the forks - then the wheel will come off.
You have to take the speedo cable off the hub first, of course.
Do not touch the handlebar brake lever while the wheel is out, for obvious reasons!!!
You don't actually need to take the wheel spindle out of the wheel, but if you do, make sure that the speedo drive correctly locates in the cutaways or you can knack it and/or the drive lugs if not in the cutaways.

Do you know the Torque Specs for the front tire?

Not sure what you mean by that.
You can't torque a tyre.
If you mean the wheel, then tighten the 13mm nuts finger tight, and a 'nip' with a correct size spanner.
They don't have to be TAF. (Tight as heck)
Same with the wheel spindle nut, just 'nice and tight' not 'swinging on the spanner' tight.
Think of the poor sucker who has to get it off next.

Make sure the threads are clean before you put the nuts on and if you have some thread lube (copaslip or similar), put a smear on. It will help the next poor sucker!!

sorry, the tightening torque for the front axel, and axel holder bolts.

1) Remove axle nut cotter pin
2) Back nut off about a full turn.
3) Loosen and remove the 4 nuts an washers that hols the axle bottom caps on.
4) Get a new tire installed (I assume that's what you are doing).
5) Nestle axle in the forks and install the bottom caps, washers and nuts. Tighten these to spec.
6) there is no spec for the front axle nut. Just re tighten it till it;s good and snug and lines up with the cotter pin hole.
7) Install a NEW cotter pin. Never re use cotter pins.

Torque specs are here:
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Can't find any reference to that in the manuals so like I suggested above, clean the threads so the nuts spin freely by hand, then just nip them up. If you use a correct size spanner rather than an adjustable wrench or similar, you shouldn't be able to overtighten the nuts. Make sure the wheel spins freely when it's all tightened up.
Personally, I would only torque bolts/nuts if they were on something stressed, like crankcase, clutch or engine internal/barrel/head fastenings or critical components.
You tend to get a 'feel' for that kind of thing after about 40 years or so!!!
The nuts on the fork end caps should have spring and flat washers on and these should stop the nuts coming loose after tightening anyway.
Get yourself a parts catalogue. They are invaluable for showing how things fit together and in what order.