What class of animals? - Bred cows, cows nursing calves(what stage of lactation?), stockers, developing heifers, weanling bulls, feeders, Holsteins...all have differing needs/requirements.
Available forages...beef cattle excel at harvesting grasses, legumes, forbs and converting it to a value-added product. Right now, I expect pasture to provide everything mine need except for salt & minerals. All grazing and no feeding here, from Feb-Nov.
Available supplemental feeds?...Depends on where you're located. Locally-sourced feedstuffs likely to be most affordable - but, you can spend as many $$ as you're willing to pay; somebody will take that cash off your hands... whether it's worth it or not is another thing altogether.
Winter feeding here consists of limit-fed hay and an appropriate amount of DDG for stage of production.
Depends on the above - and more - and what your goals are.