Actually I didn't giggle until I got to the part about you being a baseball player!
You may have the answer to your questions by now, but let's see if I can answer some of your questions.
1- How much water should be given to a plant? Is there different amounts from when you just buy it or replant or does the amount always stay the same?
That depends on several factors such as how much sun the plant gets, the type of soil it's grown in (sandy soil drains quickly, clay soil holds water), if mulch is used less water is needed as the mulch helps to retain moisture and keep soil temps more even, the plant itself as some like lots of water and some prefer it dry. Cactus like well draining soil and not too much water. Most prairie plants like coneflower, daisies, liatris and salvia prefer it a bit on the dry side.
Not sure what you mean by the second part of your question. Maybe you mean as the plant grows larger will it need more water? Probably. Small plants may need smaller amounts of water, but more often.
2- We sell plants in the containers, is it smart to re-plant the flowers or keep them in that container? What are the advantages and disadvantages to doing that?
Generally it's best to plant in the ground. Containers limit the root growth. When a plant becomes rootbound in a container it can become stunted.
3- Is there a special website I can go to to get more general info. about plants and plant diseases and stuff?
There are so many I'm not sure where to send you to. I answer many questions on several forums and I literally have hundreds of links. Even with that I often will search for info on google when I don't have what I need. Many of the chemical companies have sites but I don't use synthetic chemicals or recommend them. Sometimes it's best to search with the plant name and something like:
Coneflower + disease
Coneflower + pest
Often your local extension service is a good place to look for info. Here's their main page. You can click on 'Home and Garden' on the left and go from there.
They also have a great weed id site. You can click on 'Thumbnails' for pics.
This are pretty good sites.
Here's organic ways of dealing with plant diseases and pests.
4- Should anything be used to help grow the plant? Throwing fertilizer on it...etc etc. Would anything harm it.
I find the best thing for growing healthy plants is healthy soil. Feed the soil and you feed the plants and give them a good environment to grow in. To do that you need to add organic material to the soil and mix it in. It's best to do this to the entire planting bed or planting area, not just the planting hole. One great way to feed the soil is with compost. Compost is decomposed organic matter. Ever walk in the woods and and notice how good the earth smells? That is the smell of decomposing material such as leaves and plant matter. A balance of green and brown material makes for good compost. Greens are usually green and contain nitrogen. That would be things like veggie scraps, grass clippings, rotten fruit and veggies and used coffee grounds. Browns would be mostly brown things that contain carbon. That would be things like shredded paper (junk mail, black newsprint, brown paper bags, cardboard), shredded wood chips and fallen leaves. Since you work in a garden center they probably sell bagged compost. A 3" or 4" layer mixed into the soil makes most plants very happy.
There are also fertilizers. They are either synthetic or organic. Synthetic fertilizers like Miracle Gro and Osmocote leave behind residual salts, don't contain trace minerals and are like steroids for your plants. Using them will cause a flush of juicy growth that often attracts insect pests that like the juicy new growth.
Organic fertilizers like fish emulsion, seaweed, sea kelp, well rotted manure contain many trace minerals and feed plants gently for optimum growth. Maybe this will explain it better.
When you ask if anything will harm the plants the answer is yes. Too much fertilizer can burn the roots of the plants and kill them. That is more of a risk with synthetic fertilizers.
Putting a plant that wants full sun in a shady spot or a plant that likes dry conditions in a wet spot or plants that like lean soil (with little nutrients) in rich soil can cause harm.
Another thing is the pH of the soil. Soils can range from acid (low numbers) to neutral to alkaline (high numbers). Putting plants that like acid soil in alkaline soil will cause them not to thrive and vise versa. This will explain it better. Btw, most compost is neutral in pH and most plants prefer soil that is neutral to slightly acid.
5- Right when you re-plant a plant, should you take a precautions?
Not sure what you mean, but precautions that come to mind would be to plant when temps are below 80* F to 85* F, plant in early fall about 6 weeks before a frost is expected so the roots have time to establish, enrich the soil with compost, apply mulch to keep the soil temps even and help retain moisture and water when needed until the plant is established. If plants are rootbound in the pot the roots should be teased so they grow out into the soil. Plant at the same depth as the plant was growing in the pot.
6- What is the right way to re-plant a plant?
As I said above, the right plant in the right place. Don't plant a cactus in a wet spot, etc. Give the plant the conditions it needs. Cleanly cut off any roots growing out of the drainage holes, gently tease the plant out of the pot, tease out the roots so they grow into the soil, dig a hole as deep as the plant was growing in the pot, gently press down the soil, water well, add mulch and water again to moisten the mulch so it doesn't wick away the moisture from the soil. [url=https://www.arhomeandgarden.org/landscaping/Planting/stepbystepplantinginstructions.htm]Here's pictures[/url].
I hope you find this easy to digest and it's helpful. Don't hesitate to ask more questions.