Since you are new let me first start off by saying, practice digging your plus in your backyard first before hitting a public space.
Dig a 3 sided plug and flip it up so that the grass has a chance to come back (and stay in place), rather than digging a full circle plug.
Never use a shovel in a public space unless it's a forest, a beach, or the owner of a property has given permission.
Now onto your question..........
A pin pointer in my opinion is something that I'm glad I bought right away, and will almost never hunt without it.
The Bounty Hunter one is cheap, but it's also useless so don't waste your money.
The Garrett carrot (the orange one) is a fan favourite so I would go with that.
Get a good handle digger. People talk about the Lesche digger all the time, but I just use a hori hori knife that I got at a local gardening store and it works great. Wont bend, has a serrated edge on one side so I can cut through roots if they get in the way.
As for a pouch to carry all my finds, I use one of these........
I use one section for my good finds, and the other for the trash. I also carry a plastic bag with me in case I find some bigger stuff.
You can get different versions of the "fanny pack" or "bum bag", but I picked my up at a discount store for $3.00 and have used it for 5 years now.
You don't need to buy a sand scoop or water scoop right away (unless you plan on doing lots of water hunting), a simple shovel will do for the beach and forested areas.
If you want a water scoop then I'm sure one of our vendors here can help you out.
I use a Stavr scoop that I got from Ukraine.
The other thing you will need is extra batteries........don't leave home without them.
Good luck.