Here’s a good article on what most people do in the gym. Bottom line is don’t do random stuff to build strength. Pick a specific program. There are a few of them out there.
I started a 3×5 weight training program today, Starting Strength. This program requires a barbell, weights and a power rack. In the beginning the program consists of the following:
Lifted today (Jan 22, 2018) with my 14-year old son. We started with 45# bar for the Squats and Press. We did 95# for the deadlift.