Need advice

So I've been single for about a year and a half. My last relationship was very toxic and I know I'm not over all the trauma from it. I Also have a 3 year old who I have full custody of. I know I'm not ready for any type of serious relationship nor do I have the time but I miss being with someone not only to have sex with but I want a friendship too . I've never done casual but at this point in my life I think that's all I can manage. The only problem is I don't know how to do casual. I've always thought of dating as a means to a end. Meaning you date to figure out if you want to be serious. I dont know how to just have fun, live in the moment and not have or put expectations on it. I'm worried that if I start seeing someone casually, I might catch feelings and want something that I'm not ready for. How do I stop feeling like dating needs to lead to a relationship?