What you need to start is some know-how(and with the internet its easy to find basic beginner workouts), a pair of dumbbells, and maybe a Swissball.
If you have a gym membership and they have machines then go for it. Make sure to ask how to properly use them for your goals though. Some gyms form circuits with the machines which is quite handy for beginners... You just follow the machines working on them one by one until you finish. Then you can rest, stretch, or go for a jog.
What are your goals? What's your diet like?