Please, anyone ? American equivalent?

There are several sites that will convert everything for you. You will need to convert for each specific ingredient if you are going from grams to cups because 200 grams of flour will not be the same amount of cups as 200 grams of powdered sugar. Also, you will have better results if you use weights rather than cups. Baking is more sensitive to ingredient ratios (water to flour example). I bought an inexpensive scale on Amazon and found I get much better results with it than with my measuring cups. Then you only have to switch the scale between grams and ounces to try recipes from different regions.

Kingarthurflour.com has some good recipes & conversion charts I believe.

Best of luck with your bread making! I know you will soon be hooked on making your own as its hard to beat homemade bread with anything commercial. Here is a website that may be helpful: https://www.thecalculatorsite.com/cooking/cups-grams.php. HOWEVER, grams are a measure of weight and flour is measured in volume by cups in the US, so you aren't exactly converting apples to apples, and in baking weight is generally more important than volume. My best advice is to purchase a kitchen scale that weighs in both grams and ounces. OXO has one that measures up to 5 pounds for about $25-30 and one that measures up to 11 pounds for around $50, and there are many others on the market. Have fun learning your new skill!