Hi Netta,
Yes, they make seeds, unless it is a sterile cultivar. Many named varieties still make seeds though.
When a bulb/tuber/corm makes another bulb/tuber/corm, they are making a copy of themselves. When they make seeds, it could be a copy if self pollinated. If pollination occured with other varieties, all the seeds will be different. This is where new named varieties come from.
Some plants will grow quickly from seed and you will see blooms in the second year. Some plants take a longer time like Daffodils. That is why new daffodils are so very expensive!
Remy