When you do a shift+F part search all the schematic symbols are listed under Sch Lib and the PCB footprints under PCB Lib. Find the real physical part that you want to use first. Make sure it is from a manufacturer that has a good quality datasheet giving detailed dimensions including the dimensions of pins to the device outline (I have found a lot of poor quality datasheets that miss these dimensions out which makes it impossible to design an accurate PCB footprint). Find a suitable PCB footprint from the library or one that is near to it. Wherever it comes from, you need to check it against the datasheet anyway so open it in the PCB Lib Editor. If it's not quite what you need then, to avoid any confusion and to make it easy to find again, save it with exactly the same name as the schematic symbol that are going to use. So if the part you want is a PS2273, then save the PCB footprint with that name. Then edit it in the PCB Lib Editor and once you've checked it, save it and then refresh the list in the paets search panel, select the footprint again and then right-click Modify to add a short,  clear description and links to a manufacturer's or supplier's device page and to datasheets (some parts put the mechanical drawing on a separate sheet). Add some tags separated by semi-colons. Next repeat the same steps to find a suitable schematic symbol saving it with the exact same n

Sorry, hit send by mistake... ...Next repeat the same steps to find a suitable schematic symbol saving it, using the Schematic Lib Editor, with the exact same name as for the footprint. When you check and if necessary, edit the symbol in the Schematic Lib Editor, you must also edit the package attribute to be exactly the same as the PCB footprint name (which is now in the library so will appear when you search for it in the Package Manager). After saving the symbol, refresh the parts search list, reselect the symbol and add exactly the the the same information in the Description section and add the same tags, as you entered for the footprint. Now when you search for the part, it will appear with a complete description that everyone can see, with links to proper datasheets that everyone can check and it will be correct. This may seem like a lot of work but by the time you have created your footprints and/or symbols in other ways such as by cloning a similar footprint and then simply editing the package attributes of each instance of the schematic symbols - and checking that you have done that correctly for all instances - you might as well do it this way. If you do not want to have your footprints and symbols shared publicly, you can either copy aand paste them to your own private schematic and PCB sheets or (because it is complicated to go back and edit them to create new versions when they are stored this way) simply create a one person Team which will create library areas that are private to the members of that Team.