Building database for marketplace - where to start?

Where to start to build a good, useful database for a website that is similar to this one: https://zoptamo.com/uk/s-crossfit-c-uk ? Also, database optimisation tips are appreciated too (base should be fast and records should be easy to find).

 

Create a plan for the database. All the tables, all the relations among the tables, and so on. Then you will see where you need to have indexes, where foreign keys should be used, where you can get away with using internal triggers, and so on. Also, stored procedures will aleviate some of the pressure on the database, depending on type of usage. If this is a product-database, you will mostly just pull content from the database, and maybe change stock-amounts. The rest will be mostly storing of orders and such, again not very demanding.

 

Oh, huuuge thanks for replying and this number of useful advices Also sorry for late reply here