Ive linked to a spreadsheet to bring in data but i can’t seem to amend the Table - e.g. to make a field an index
A database which holds data in a spreadsheet file is a pseudo database. You can use it as a data source, but for anything beyond basic data extract you should import the data into a proper database solution.
The embedded db engines are better in this respect, but still limited in some ways. For single user/single access instance either should do fine. If you need the latest functionality, multiple concurrent access or better performance, install either of them, or any other DB server software, as a standalone DB server.