Sharky, your first question refers to plants that grow from bulbs. These are usually the commonly available Nymphaea sp. They are relatively undemanding plants that do well in low to moderate lighting conditions. The bulbs go dormant sometimes. I'd trim the leaves that reach the surface to prevent them from covering the light needed by your other plants.
What fish do you have? How big is your tank? What is your lighting capacity? These are three factors that have to be considered if you are attempting to keep plants.
It is wisely recommended for beginners to start with plants that are relatively easy to keep and are undemanding without the use of high lights and CO2 injection. Remember to take it slow and easy as it is important that a good and slow start will make your experience a fruitful one. For a good start, try to get floating plants such as Pistia stratiotes, hornworts, water hyacinths and duckweeds. Keep your tank open-topped as most of the plants mentioned do not like condensation droplets forming on their leaves particularly the Pistia stratiotes and will eventually rot quickly. Although the duckweeds are firm favorite salads by most fish, by the time they have reproduce enough to sustain their number, they will work excellently in consuming nitrate level thus improving the water quality like other species of floating plants suggested although nothing will still replace the water changes as the top method for reducing nitrate and other nutrients. The hornworts are unlikely to be consumed as they prickle the mouths of the fish as it does with other fish that are urged by the temptation to eat it. Duckweeds, water hyacinths and P. stratiotes reproduce rather quickly through runners and can quickly carpet the whole surface area so be sure to trim them out when necessary. Hornworts reproduce by cutting and with their brittle leaves and stems, they can be messy and can clog some filtration systems.
Java ferns, Java moss and anubias are also tough choices. Although Java ferns and anubias are low light plants thus making them easier to keep than most species, they are extremely slow growers. They need to be tied with nylon thread, string or fishing line into place on a decoration but not too tightly that the rhizomes become severed. Java moss, on the other hand, do not need too much attention as it will readily attach on anything and carpet it completely so be sure to trim them down if you do not like a rather bushy plant area.
For rooted plants, a good suggestion would be an array of Cryptocoryne sp., Echinodorus sp., Vallisneria sp., Sagittaria sp., Egeria densa, Egeria canadiensis, Hygrophila sp., Nymphaea sp. And Aponogeton sp. As all are rooted plants, be sure that these are planted firmly to the substrate and the white crown is not covered entirely or the plants will suffer Cryptocoryne rot which involves the plant melting although it will eventually recover but this may take some time and is best avoided. Cryptocoryne species are far more prone to Cryptocoryne rot than anything else so avoid transplanting them around too much. Finalize the layout before you try to stick them where they should be. The first four plants mentioned reproduce by runners and can quickly carpet the setup in time depending on the conditions provided. Hygrophila sp. and Egeria sp. can be reproduced by cuttings similarly with hornworts although the latter is not purely a rooted plant and is best kept afloat. A lot of goldfish favor the Egeria densa so do not be surprised if you find this plant left with a stalk instead. The leaves are too much for the goldfish to resist. The last two plants suggested Nymphaea and Aponogeton reproduce by bulbs. The Nymphaea sp. especially is an extremely beautiful plant with lushy leaf growths and even sprout flowers on the surface if allowed so be sure not to enclose your tank with a lid if you want to see the flowers sprouting and adding up to the beauty of the setup. The bulb can be left on its own although burying it halfway down will help it establish firmly its ground. To allow the young leaves to grow well, the leafy stalks that reach the surface may need to be trimmed down and this also helps prevent clogging of the surface with too many floating plants.
If you do not opt to try live plants, you could use silk plants. Make sure your choices of fake plants do not have sharp pokes, corrosive metal strips and anything else that may potentially injure or kill your fish. Some fake plants have been known to be responsible for the tattered fins. This must be avoided if you want your fish’s fins intact.