I think what people mean when they say everything is political is that the actions of our politics shapes just about every aspect our lives. You might think that driving to a restaurant to buy a meal isn’t political, but everything about is the result of decisions of voters, politicians, and bureaucrats. How smooth the drive is dependent on how much money your city allocated tax money for road maintenance and how city planners decided to lay out your area. The laws and regulations, and the competence of the enforcement, on safety effect your chance of getting sick. The laws on tax burdens, labor laws, minimum wage laws, trade agreements, etc. factor into the price of your meal. Your level of disposable income to go buy meals is effected by those labor laws, wage laws, cost or rent or a mortgage (which itself is effected by city planning of what types of space can be built where), and on and on.
The point of “everything is political” is to snap people out of the mistaken idea that politics is just abortion, voting, gun rights, and tax loopholes.