Thanks for your post.
With more information, I can´t tell you many things.
You can use a default WooCommerce simple product if you sell any number of meters.
However, if you want to sell distinct premeasured products (like 10mts, 20mts, etc.) and keep the stock available synchronized between them, you can use ATUM Product Levels to do so.
You can set the number of available meters as a BOM product and link it to the distinct products to sell. You can make the BOM product sellable if you also want to sell custom lengths.