Can i die from lymphoma if i ignore it?

Yes, it is possible: There are different types of lymphomas which can range from slow growing to rapidly progressive. All lymphomas, even low grade can lead to death if not treated.

Yes: Ignore lymphoma and it will kill you, unless you die of something else first. Depending on the subtype, it can take either a few days or many years. Many lymphomas are curable and all are at least somewhat manageable today.