It is very flexible- start with it.
If you are just starting out, HC-110 will do you fine. It is a thick liquid concetrate that if undiluted, in a cool dim place last a very long time, like many years. Even once slightly briown it still does the job.
The standard starting point for many films is found on the 'massive film development chart' - google it. HC-110, likely at dilution B, will in all likelyhood be one of the develioper listed.
Frequently the tines for dilution B are too short to allow even development in a small tank. I do what some unoficcially call "Dilution H" in these cases - dilute it twice as much as Dil B, and then develop for twice as long as a starting point. Search for an article by Barry Thornton - The Unzone System for further simple to implement ways to bring the B&W film and printing process under control for you to get predictable results.
There are thousands of developer options. Don't worry about them yet. Get the rest of your craft under control, using one developer for film, and HC-110, or the Ilford equivalent, will do just fine. They don't change characteristics like a gallon of mixed up D-76 can do for you over the course of a few months.
Don't dilute the syrup into stock solutions like the instructions on the bottle suggests- this wioll start the oxygen deterioration process - the developing agent will pull the oxygen dissolved in the water and oxidize, rather than oxidize on the film like we want.
Get a medicine syringe, like used to measure out medicine to young kids. It will be calibrated in 1-10ml or so. Dilute the required amount straight into the water for the working solutions. I got a litre bottle of the ilford stuff as part of an enlarger lot a few weeks ago from Craigslist. I calculated that it could make up something like 270 500ml working strengh solutions.