Hey, as a fellow closet witch who now lives at college I have some advice to share. I’m just gonna take things one by one and you can take the advice you like and leave what you don’t, this is all my opionion and experience :).
While you certainly don’t always need once ( unless you want to worship a diety, then it’s a little more important) an altar can be a very powerful tool. I had an altar on my beside table for years, and it just looked like a collection of jars, books, trinkets, and candles arranged in a pretty way. You can enchant items on the altar for protection and make that space a center for your wards, and you can use it as a space to prep and cast spells.
Your altar can also just be a space where you do meditation and magic, you don’t have to have things. It could just be a windowsill or a part of the floor that you sit on.
Short answer, no. Slightly longer answer, magic and paganism are two separate things that often interact but are not the same.
Gods and Goddesses are powerful beings who can obviously be helpful when studying magic, but ultimately they aren’t the only option. I have spirits, ancestors, and familiars who I call upon sometimes when I’m working magic, but I don’t have a diety or a Patron. Each persons path is different, and each person who does magic is going to have differ experiences and meet different spirits.
At least in my tradition, magic is just you trying to align yourself with the energy of the universe and the environment, or you trying to convince those energies to help you do something or get what you want. So while dieties are wonderful ( and many of my friends worship Greek dieties) they are not nessasary for magic.
My list would be at least Two methods of divination, a notebook and access to the internet.
With these, you can begin to research and learn about magic, and also begin to plan spells and make charms. There are so many books on the internet about magic ( I would recommend the three books of occult philosophy by Agrippa, dm me and I can send a link to a pdf) I would try to steer clear of “instructional” books or new agey stuffy. There’s nothing super wrong with either of those, but they can be a bit stifling and a hinderance to you growing your own unique magical practice.
Read as much as you can, and when you decide to do magic, you can use you what you have on hand. I spent a year using embroidery to make protection charms, and I STILL use them. You don’t need fancy ingredients or candles or incense at the beginning. Two forms of divination, along with your research can help you figure out what to use, and how to cast successful magic.
My suggestion is first and foremost MAKE YOUR OWN DIVINATION TOOLS!!!!!!!!!!!!!!
Nothing can describe how powerful handmade divination tools are You can use playing cards, dice, a pendulum, tarot cards, bones, sticks, charms from jewlery, food, and a million other things for divination. If you are worried about getting caught, you can just say it’s dice and playing cards, or whatever else.
BE CREATIVE WITH YOUR MAGIC! Make it all your own. If you like to knit or sew, or you like to dance or write poetry, MAKE IT A PART OF YOUR PRACTICE! Don’t do spells you see on the internet, becuase a lot of them won’t work, or won’t work for you. Write your own magic, write incantations and chants and mantras and whatever else. If you don’t have glass jars, use hand sewn pouches for your charms if you want. OR, do something else that you think of. If you make your own magic, I PROMISE, that you will be more successful.
Study a LOT, and find people to study with. Find people, online and irl to talk to about magic, share what you are reading, what you have uncovered during meditation, what spells you are writing, what the spirits you met have told you, or whatever. Talking to people will help you understand it better, and they might be able to offer you some information you wanted to know.
GO OUTSIDE!!! There is a whole world of nature spirits. spells, free components, and all kinds of other magic outside. So spend time ( Safely!) outside.
There are certain practices that are close to non-initiates, like hoodoo, African Vodun, brujeria, Haitian voodoo, and judiaism and these practices are commonly called closed pratices. These groups often don’t share thier rituals, or the contents of the ritual won’t work for the non-initiated. So firstly you shouldn’t steal or use spells from these practices becuase it’s appropriative, but also they probably won’t work, or will turn out poorly for you.
Best advice is “ read everything, but write your own magic.” It’s ok to study practices that aren’t yours for what they might be able to teach you about magic. But you should never steal spells from pratices you aren’t initiated into.
Avoid summoning or fucking with any entity, diety, energy, or spirit you aren’t capable of warding against/ banishing.
Avoid demonology, unless you want to spend several years and or several thousand dollars to do it according to grimoires ( for safety reasons)
Don’t do magic unless you have a clear method of reversing it in case you fuck up the spell or change your mind.
Study alchemy, and classical philosophy, and learn how to do trans substantive magic and how magic works. Those will help you the most!