What's your question? Ask

Shallots adapt well to growing in containers as long as they are well-drained. You'll have to water and feed them a little more--the way you do any container plant. As a rule of thumb, for the smaller more shallow-rooted plants, like shallots, use a minimum container depth of 12", and for the larger varieties 18"-24" deep.

You can. They will be more expensive this way, but if you can't find them from a seed company, there is no reason you can't do this.

It sounds as if they may have bolted. Here is more information: https://www.gardeningknowhow.com/edible/vegetables/vgen/what-is-bolting-what-it-means-when-a-plant-bolts.htm

Your plants have bolted. These articles should help:
https://www.gardeningknowhow.com/edible/vegetables/shallot/tips-for-growing-shallots.htm
https://www.gardeningknowhow.com/edible/vegetables/vgen/what-is-bolting-what-it-means-when-a-plant-bolts.htm

Shallot flowers are round like an onion, but they don’t get that distinctive scape appearance. Grow shallots as you would onions. During the growing season, some of the leaves may be cut at the ground level and used as green onions. Plants that are not heavily cut will proceed to form many bulbs attached together forming a clump. Shallot bulbs often develop on top of the ground.

Here is an article that you may find helpful: https://www.gardeningknowhow.com/edible/vegetables/shallot/tips-for-growing-shallots.htm

This article will help: https://www.gardeningknowhow.com/edible/vegetables/shallot/tips-for-growing-shallots.htm