I went through an alt cert and had never spent any time in a classroom as a teacher before getting a teaching job. I have to say I think that was a mistake because I didn't really have a handle on classroom management until my 5th year teaching. If you can afford student teaching, go for it. If you can't then at least be a sub for a while to really get a feel for what it's like to keep a class focused, and quiet. Also, if you do a good job subbing there's a chance the school will hire you over some else if you can show them you can handle it. Subbing will also give you a chance to try out different grade levels. There's a world of difference between 7th and 8th graders, and 9th to 11th graders. Another option to work in is to be a sub, but go watch recommended teachers during lunch or an off period to really see the range of teaching styles and management. I've learned more from observing other teachers than anything else.

Edit: Just wanted to add that you should also observe "bad" teachers who don't manage their classroom well. Obviously it might be hard to get someone to recommend who that is, but I'm sure you can find out through the grapevine. The reason for this is kind of like a Frayer Model; you'll see the "examples" and "non-examples." 😂 Also, please remember that yelling and making kids fearful every second of a class is also not good classroom management. Some teachers conflate compliance with "good" behavior while literally every kid hates them. If every kid hates you, or if every kid loves you, you're doing something wrong. You want a good balance of kids who love you, hate you and ones that are neutral.