Need answers!

I just found out I’m pregnant with baby #3, With my first two pregnancies to be honest I didn’t work out other than going for walks. I have been working out and using the Beyond Raw Lit pre workout mix. Obviously I can’t take it now since I’m sure it’s not safe. (1) But I was wondering if there’s a pre workout mix that’s safe to use during pregnancy? Or if there’s ways to make something naturally that won’t harm you or the baby that will give you energy and pump you up before a work out? (2) Also is there any supplements you can take while pregnant to help you burn fat as you work out? Since again I can’t take what I was taking before. And last but not least, I’m no more than 3 weeks, So yeah I’m on the first trimester. (3) Is there any specific work outs I should stay away from? What are the best workouts to still burn that are safe?

Answers will be greatly appreciated. Thank you!