“To toe the line” figuratively means to conform, submit to authority, obey the rules. The expression started out literally meaning to put your toes against a marked line. It has been used in the discipline of sailors and in sporting events with a starting line among other things. It dates from the 1800s, when “to toe the mark” was also a common expression.
“To tow the line” is not a common expression, but it would mean to drag a rope or something similar behind you.
![Monday Muddle: toe: (noun) body part; digit of the human foot; part of footwear that covers front of foot; (verb) push, touch or kick something with front of foot Part of the expression "to toe the line". tow: (verb) pull, drag or haul something (often a vehicle) behind you; (noun) the act of towing; rope or line used to tow NOT part of the expression "to toe the line".](https://plaunt.com/wp-content/uploads/2021/07/962FC0BE-52C1-4860-B6E1-08C4A0F9505A.png)