That question cannot be answered without context. To use "previous", you first must establish establish a reference time. For example, you could say "In July of 1760, Beethoven wrote a piano concerto. The previous April, he finished a symphony. In that case, "the previous April" refers to April of 1760. The one time I can think of when it would make sense to say "the previous April" without providing any context would be if you were talking to someone in April. If it is April, and I say to you "Yulia, the previous April we went to the park. Let's do it again" the meaning would be clear. Saying "previous April" helps to make it clear that I am not talking about the current month. In that case "previous April" means the same as "a year ago". However, if it is August 2023, and I say "the previous April" without any context, it would make little sense. Different people would interpret it in different ways. It would be better to just say "April" for April 2023 and "April last year" for April 2022.