Wheel Wobbles and Rubs on Brand New Bike?
The issue you are having is the wheel is "out of true".  This is caused by uneven spoke tension.  It can be adjusted, but it's easy to go wrong here and make it worse if you don't know what you're doing.

Most good bikes are bought from bike shops.  This allows the shop to properly assemble and adjust the bike.

If you know someone who can do it (and possibly teach you) that would be your cheapest option.  (six-pack of beer?).  Otherwise, I recommend you take it to the bike shop.

If you do decide to do it yourself, you'll need a spoke wrench and a lot of patience.  There are youtube videos that can show you how.

I still recommend a bike shop.  Most bikes from stores are not properly assembled at all.  Many times the bearings have not been greased.  The "cheap" bike seldom is actually cheap.