You don't need any equipment to have fun with stamps. If you just want to make art with your stamps, place them in journals or use them for projects then you don't really need anything but the stamps.
If you want to investigate the stamp then the most useful piece of equipment is a magnifying glass.
If you want to keep your stamps in the best condition then you should try to not handle them and use tweezers.
If you want to store your stamps so that they don't get damaged then a stamp album or stock book is the best solution.
To attach your stamps to pages without damaging them, then you might also want hinges and mounts.
There are other items that some stamp collectors have but some of them are expensive. These are not needed to enjoy the hobby.
Catalogues - you don't need to have the most up to date catalogue. You might find some older copies. There are also some online catalogues that are free to use.
Perforation gauge - only needed if you really need to know the difference between some stamps which were issued with different perforations. It can make a difference to the value of the stamp.
Stamp drying book (for placing stamps in after soaking) - paper towels can be used.
Watermark detectors - only needed if you really need to know the difference between some stamps which were issued with different watermarks. It can make a difference to the value of the stamp.