SEC Tournament is meaningless for teams in the top 4 most are always National Seeds anyway. Nothing they do effects that.
But as mentioned the Top 4 in the Conference get byes into the double elimination round and 5-12 compete in single elimination then it switchs back to single elimination after the double elimination round when 4 teams remain.
Note: only 2 teams have ever won both The SEC tournament and CWS (2009 LSU and 2019 Vanderbilt). Winning the SEC Tournament is usually the kiss of death in the NCAA tournament as it taxes your pitching. More teams have won the CWS by getting eliminated early than by winning it (2010 & 11 South Carolina and 2014 Vanderbilt)
Tennessee has never won the SEC Tournament in Baseball