No, they are quite different.
A conference is a meeting. Usually people will give short talks, or show posters about research topics. Those talks will often be arranged in groups around a similar theme. The idea is that colleagues meet to present and discuss their work.
A lecture is a formal talk. It is mainly educational - an expert will talk on a topic that they are familiar with. Here, almost all university classes consist of a lecture, where the teacher talks to the students about a particular topic. There are also public lectures, where again an expert will give a talk or presentation, but usually on a topic of more general interest. A lecture is typically 1 or 2 hours long.