I want to move my website https://mysushi.ph/ to a simpler platform like WordPress so I can make small changes myself and don't be dependant on developers (e.g. title meta changes for SEO, posting blogs) the problem is I don't have a clue how to do, this can someone help me understand the process.
There are many sites that can help you become more familiar with how WordPress works. The WPBeginner site (search for it) is one of them. There are tons of end-user-level tutorials. You don't have to be a developer to use WordPress. You can use the default theme to get started. Or look for a theme that might be to your needs - there are tons of free ones.
There are tutorials for developing themes, but you don't need those (for now). And you don't need to know programming to create a site. Tons of plugins are available for you to find one that meets a specific need.
This place is for developer-type questions. And the more details you can provide on what you are asking will give you better answers.
For now, ask the googles/bings/ducks for some beginning WordPress tutorials. That should get you started.