Don’t take this badly, but we’re all racist (or at least some kind of “-ist”) because the Human Cognitive System naturally uses simplifications to be able to interpret and take decisions on the world around us, including on people, so boiling people down to some “group” on something very visible (gender, skin color, clothing, the kind of words they use, how they move and speak and so on) and then assuming they’re “like” some idea you have about people from that group (i.e prejudicing them) is a natural tendency.
Further all those ideas one has about “people from a group” are invariably bollocks and often absorbed subconsciously through the same mechanisms as used by Marketing to influence people.
All you can do is be on the watch for you yourself making such unfair judgements on others due to your own mental simplifying and categorizing of people, and stopping it when you notice it and refraining from acting based on any judgements that cannot be traced to what that individual has done and said (all of which if Cognitivelly a lot heavier than “categorization and assumption”).
So de facto racism isn’t about holding prejudiced ideas it’s about a whole range of how much effort you make to treat people based on their individual actions and words alone and stopping yourself from using categorization to judge people (and even decide what to tell them and how to act towards them).
Note that I’m not trying to excuse racism here: I’m saying you can’t simply deem yourself “not a racist”, because it’s the result of natural human tendencies so ethernal vigilance is required not to act so, even if your intentions are pure.
All this to say that “racism” (or more generally categorizing people and making prejudiced judgements on them base on that category) really isn’t the right thing to claim has no middle ground, because it’s a range and a person’s position on it boils down to how much effort that person makes to try and stop themselves from letting the “conclusions” coming through such cognitive paths influence their words and actions.
Or to put things in another way - people who practice violent acts against others purelly based on the skin color of said others are very racist (extremelly so) and people who have different expectations on the behaviour, life status and even worth as a person (i.e. presumed good person or presumed bad person) of others based on their skin color are racist too, though if they don’t actually act on it or verbalized it, they’re way way less racist that the extreme ones.