How to shrink SQL Server Log File Size?

To start off, I am a Software Engineer - nowhere near a DBA. I can install SQL Server and setup a simple SQL Server database, which I have done. I setup a simple SQL Server 2016 database on a client's web server (Windows 2012 R2) to store some data for a new website being deployed on the server. It started off as a very small database with a few tables. It has quickly grown to have a few dozen tables, several of which have thousands of records. The database is basically being used to import data from an external API and store it locally so that it can be accessed frequently without performance issues. All of the data imports are up an running without issue. However, I have noticed CPU spikes on SQL Server. More importantly, the log file for the database is up to 33GB. I am very afraid this log file is going to end up using all of the available disk space and crash the server. I need to know what I can do in the short-term (until we get a real DBA in here) to prevent this from happening.