Hello,

Most of the study that you have to do as a CSE student is to be conducted on a computer system since there will be a lot of coding and development of software based on your specialization. Hence, most CSE students prefer getting a laptop which can run heavy codes and process multiple languages such as C++, JAVA, C, Machine learning, etc. It is better to get a laptop as a first year ECE student also, since there is technical aspects to it as well.
Therefore, you should go ahead and invest in getting a laptop as a first year. Additionally, you can also wait for your second semester to start so that can analyse your syllabus properly and get a laptop according to the kind of capacity it should ideally have.

Hope it helped.