In Pa. What does the surviving spouse get 1/3 or half, on a will made before marriage and left of the will, and not having any kids with the him

Most states, including Pennsylvania, have a law that allows a surviving spouse who is left out of a Will to claim an "elective share" of the deceased spouse's estate.  This must be done by filing an elective share claim with the probate court and I believe it needs to be done within 6 months of the deceased spouse's death or date that the Will is probated.  There is a somewhat complex formula for what assets are counted in this calculation, but it does not include life insurance or retirement funds.  If the deceased spouse owned assets jointly or died owning significant assets, it would be worth the wife's money to consult with any attorney.