Hi,
I thought I would add in my 2 cents since I am doing barbell training (squats, deadlifts, bench press, and overhead press). I believe Alan Thrall has a really good video on the accuracy of solid steel plates.

I'm aware that for rubber bumper plates, the manufacturer can make it so that the weight is right on the money. However for steel, I believe the accuracy on the 45-lb plates can vary between +/- 5lb. It's quite a variance if you're squatting with multiple 45's.

My program is 2-3x per week, where I go up 2kg (4.4lb) on my heaviest weight (work set). I warm up, and then squat for 3 sets of 5 reps on my work set. For the deadlift, I warm up to the work set and then deadlift for 1 set of 5 for the heaviest set.

If anyone needs any help getting started with barbell training, let me know. If you have access to a gym with a power rack, I would recommend getting weightlifting shoes that have a 20mm heel height (only use the shoes for barbell training), get a notebook, and possibly get a set of 0.5lb (qty: 8) fractional plates so you can go up 1-4lb (instead of 5lb) on your overhead press.