Obviously the naval side is unquestionably Britain, but I think OP was perhaps thinking of the pre-Crimea British army, which had an establishment of 130,000 and almost no reserves. By the early 1860s, looking just at the UK and not the empire, the army has an establishment of closer to 220,000; the militia, refounded more or less from scratch in 1852, brought more than 95,000 men to a minimum of 21 days training in 1863; the volunteers have an enrolled strength of 162,935, and the yeomanry have around 15,000 men. These forces are armed with weapons that Confederate soldiers fought to get their hands on, like the P53/P60 Enfield, or probably didn't know existed, like the Armstrong 12pdr.
Looking beyond the material aspects, the British regular army is a long service force (standard enlistment term of 10 years with the option to re-enlist for another 11; most did); the effect of having experienced NCOs rather than having to build from scratch should not be understated. I think we also underestimate the effect that Crimean and Indian service had on the quality of both the senior leadership and the battalion-level officer corps: British officers who purchased their commissions weren't inherently any less competent than Confederate officers who were promoted through political influence or election. We also play down the fact that the British army had a significant programme of
musketry training, which there wasn't time, experience or money for during the American Civil War.