hi ,load bearing is if the ground floor wall is of solid construction and it continues to be of solid construction through first floor to ceilings. if the wall above is a stud work wall then it is not load bearing,but generally is supporting ceiling joists which normally run the shortest distance of any given room dimension. if not load bearing then a catnic heavy duty lintel will be sufficient . if not load bearing the ceiling to either side of the wall to be removed will need to be supported by acrow props and planks. if load bearing then acrow props and needles,(temporary support steels) will need to be used. and an rsj(rolled steel joist) will have to be used to the dimensions of a certified engineer. weather load bearing or not the lintels/U beam,should be bedded in mortar 150mm each end so 300mm in total wider than proposed opening and normally on cast concrete pad stones. either solution will require fire proofing prior to plastering and will need to be inspected and signed off by a local authority building inspector. I hope this helps.