I understand the learning curve. I work with a SQL Server and SQLite files regularly now and the best thing that got me over the hump was perusing resources outside of MATLAB for SQL sytnax. Try W3 schools as an approachable first.
Also reccomended is to make yourself some easy, repeatable unit tests to manage database connections (open / close) and deleting old files so you do not step over previous sqlite files / connections.
Along the way here is a simple way to create and work with a database in MATLAB persuming you have the Database Toolbox.
clearvars
dbfile = "tst.db";
if isfile(dbfile) delete(dbfile); end
conn = sqlite(dbfile,"create"); % makes a sqlite file for you
% get an interesting table
LastName = {'Sanchez';'Johnson';'Li';'Diaz';'Brown'};
Age = [38;43;38;40;49];
Smoker = logical([1;0;1;0;1]);
Height = [71;69;64;67;64];
Weight = [176;163;131;133;119];
BloodPressure1 = [124; 109 ; 125 ; 117 ; 122 ];
BloodPressure2 = [93; 77; 83; 75; 80];
T = table(LastName,Age,Smoker,Height,Weight,BloodPressure1, BloodPressure2)
% write it to the database
tabname = "Data";
sqlwrite(conn,tabname,T);
% read it back
Tread = sqlread(conn,tabname)
% read with a row filter
rf = rowfilter('LastName');
rf2 = rf.LastName == "Sanchez";
TSanchez = sqlread(conn,tabname,"RowFilter",rf2)
% a more advanced gem when you are ready
sq = sprintf("SELECT * FROM %s",tabname);
sqlopts = databaseImportOptions(conn,sq);
% preview the data only (first 8 rows)
preview = sqlopts.preview
