Welcome to Pixalo Brandon
You have a good basic kit there. The lenses cover a good range of focal lengths so you ought to have something for any situation.
If you like nature shots, the long end of the 75-300 lens will be very useful, so I would not rush to return it.
As you become more familiar with the kit you have, you will find limitations. It is then you can think about expanding the lenses you have, and get them to the attention of Santa, or anyone who will be buying you birthday gifts.
Using lenses with long focal lengths is a skill, and macro is probably the most difficult, so I think you would do best by starting off using your new kit rather like your old Powershot, then pushing out from that base.
If you want any feedback on your pictures, post them up in the
gallery or the
sharing forum. The critique forum is for more detailed comment on one picture.
There is a guide on how to post pictures
here.
Finally, if you want to know anything, just ask. No-one here will put you down or think that you ought to know stuff already.