Thistle. Easy to dig out because roots are generally shallow. It's helpful to wear gloves made for pruning roses as they protect from the prickly spines.

Likely thistles are common in the area. The seed blows around readily. So keep an eye out for more thru the coming years. Easiest to remove the smallest size.

Canada Thistle. Not an easy weed to get rid of. It develops an extensive root system and will put up new plants anywhere along the roots. Listed as a noxious weed in many states because of its invasiveness.

Applications of glyphosate in early summer as it reaches the bud stage can be quite effective, also applications in September shortly before frost can be very effective at weakening the roots so that the winter will help kill the plant. Applying at these times under the right conditions can eliminate nearly all the plants, although it takes repeated applications to any regrowth to finally get rid of it.

Keeping them cut off at the soil surface will gradually starve the roots of nutrients and they will die, but you have to be committed to chopping every plant off that comes up as soon as you see it. This probably works as well or better than using glyphosate, but takes more labor and may take a bit longer.

There seldom is a good reason to spend money on much less apply any "weed" killer product when mechanical removal of most weeds is really simple. Just use some good, heavy, gloves because thistle does have prickly burrs.
Because of gross overuse many of the target "weeds" are developing immunities to glyphosate products so they are not as effective anymore and those same products are known pollutants of our planet.