Does using one 5000 pound thrust engine give the same amount of thrust as five 1000 pound thrust engines? I am asking in terms of effectiveness not efficiency. Do the two different configurations produce the same amount of thrust?
Thrust is additive. If you want more thrust, adding more engines or scaling up the size of your engines are both valid ways of doing it.
There is a balancing act you have to make, however.
At one extreme, single large engines can have unstable exhausts where the combustion products 'stick' to one side of the nozzle, to a first degree of approximation similar to how a shower head when not turned on fully will run in a single stream rather than many small jets. The Rocketdyne F-1 engine used on the Saturn V is often considered the biggest practical size of engine. The Saturn V used 5 such engines, which meant that if one were to fail, there'd be very little in the way of backup.
The other extreme - with many smaller engines - presents different complications. The N-1 rocket, designed to be the Soviet counterpart to the Saturn V in terms of mission and launch capacity, used 30 smaller engines in its first stage. The plumbing alone was a nightmare to solve. The more engines you have, the higher the chances that having one fail catastrophically will result in the destruction of the entire craft. The N-1 rocket flew four times and exploded four times, and it is thought that the complexity required for so many engines is at least partly to blame.
The SpaceX rockets use a large number of smaller engines. The Falcon Heavy uses 27, whereas the upcoming Starship rocket will have somewhere between 31 and 38 engines, depending on what mood Elon Musk is in on Twitter at the time. It seems like they've ironed out whatever problems the N-1 had when it came to plumbing complexity and so forth.
Ignoring plume interactions the propulsive effect of an engines thrust does depend on the spacecraft's center of mass being along the line of thrust. If for example a single-engine spacecraft vectors its thrust slightly to turn there is a tiny loss of linear acceleration as there is now angular acceleration.
For a single-engine craft is small because the rocket would spin out of control if it wasn't.
Now if there are multiple engines then you can point them in different directions because the torques can cancel. In this case the thrust available for acceleration of the spacecraft is reduced by the factor $\cos(\theta)$ and these reductions are usually referred to as "cosine losses"