Welcome to diving!
To give you good advice on what gear you should look at, we need to know what kind of diving you will be doing. Are you going to dive locally? If so, you'll be wearing heavy exposure protection and you'll need significant weight. There, a steel BP is ideal, and you might even want to look into the Deep Sea Supply SS backplate to which you can attach weight plates to make it heavier. This is what my husband has, and likes very much.
If you are only going to do vacation, tropical diving, you won't be wearing much exposure protection, and you may want to look into an aluminum or kydex backplate, to minimize luggage weight concerns.
Tobin George writes a lovely explanation of how to calculate needed lift in a wing, and you can read one of those
here
There are a number of manufacturers of backplates and wings. To be DIR, you want to avoid anything with double wings or bungies around the bladder. You want a relatively short corrugated hose, and no pull dump on it. You don't want knobs on the end of the butt dump pull.
You can look at Halcyon (good quality, but expensive), Oxycheq, Deep Sea Supply, Golem Gear and Agir setups. I recommend DSS, because I think their customer service is extraordinary.