Can I scheluded test?

I want to know if I can program a test a/b

You can do that using the Broadcast feature.
When you compose your email there will be an A/B test option on the left side of the screen.

If you are trying to A/B test automatically inside the campaign builder, you can set up a decision diamond and manually segment people to put through 2 different sequences, or, if you want to do it automatically, PlusThis has a tool that can help with that.