Bags are best crocheted from cotton yarn because it keeps the bag nice and stable in shape and doesn't stretch out as quickly.
The technique of "Tunisian crochet" is especially well suited for this.
It's very easy. All you need is a Tunisian crochet hook (available in craft stores) and, of course, cotton yarn.
Here is a particularly simple model that is crocheted in the Tunisian simple stitch:

Since only a rectangle is crocheted here and the bag is made with gradient yarn, you can focus entirely on the new technique. It is explained in detail in the pattern. Then the bag is folded origami-style and sewn together. Your new market bag will be ready in no time!
Here is the pattern: Origami Bag.
Would you rather crochet conventionally? I also have a pretty bag for you that you could give to your mom for Mother's Day, for example:

The bag is worked like a net and is very roomy. This also makes it wonderful as a beach bag, since the sand can trickle through the holes.
Here you only need to crochet double crochet and chain stitches. There is a graphical chart for the heart with the lettering. It is also described round by round in words.
Click here for the pattern: Bag "Mama"