Do it right or don't do it at all! Don't be afraid to spend between $300 and $400 for a decent light. Your light will play a big part in overall quality and yield. Get a Tent on Amazon a 3x3 is a decent size and most lights in the price range mentioned will veg and flower that size. A 2x4 tent is ok, but coverage will suffer on the ends if you skimp on the light. As a newbie a 2x2 may not give you the yield to make it worth the investment. a decent 3x3 on Amazon should set you back $75 to $100.
Tent and Light budget $375 to $500!
Now you need to think about privacy. If you don't want other people to smell what's going on then measure the room the tent is in and clean the air in the room as apposed to filtering just inside the tent. You want to get hot air out of the tent, but keep the room itself odor free too. From my experience I wish I had went with a 6" inline with a medium or tall boy carbon filter, rather than a 4" inline fan with small carbon filter. At a minimum $150 for a 4" inline fan with Tall boy filter or my choice is $230 for a 6" online with XXL carbon filter. A fan speed controller will set you back $30, don't forget it.
Fan & Filter budget $180 to $260
Now you want to set up your environment as a newster soil is a no brainer. Soil is most forgiving of errors. In a 3x3 go wit 4- 5 gallon buckets and two bags of soil in 1.5 cubic foot bags should run you about $30/40. The buckets shouldn't be more than $5 each. Fox Farm Ocean Forest is a decent starter brand because you really wont have to worry about adding any nutrients for the first 4 weeks. Nutrients, keep it simple many people will tell you many different ways, but your budget tells you best. A good set of nutes to start with may be a GH starter kit, it will have everything you need for a full grow and runs about $45. I personally liked Natures Pride veg and bloom soil amendment's one teaspoon per gallon of soil per week and forget it. natures pride will set you back $45. That's all you really need, but you will want more if things are looking good. So now figure on a bloom booster of some kind, you can grab a small bottle of floralicious for about $4 and Molasses for $3. If your budget is still good splurge on a 8 0unce bag of recharge it will help stabilize PH and encourage strong overall plant growth. Recharge will set you back $30 and you wont regret it.
budget for grow supplies $132 to $142
The last two things you need are water and seeds. For water a Pur filter on your tap runs $30 and works fine for a soil grow. You can go more elaborate, but think of it like your first car. Your first car is cheap cause if you crash you don't have much unto it and it cost less overall to maintain. As for seed look around a bit you can get good seeds from places like north atlantic seed co for under $70 shipped to your door. They also ship fast.
Budget $100
Lastly you can turn your lights off and on with a timer for $15, or if you have a google home or Alexa you can buy a $10 smart plug and set your lights up on smart schedule. Also you'll have a lot of small stuff to buy like temp/humidity monitor $15, depending on the tent you may need to buy flanges to connect the fan and ducting. If you buy a 4" fan you may need to buy a 6" take off and 6" to 4" coupler together they run around $30 plus you need the ducting to connect to the fan $15 for about a 12' run, then grab some tape to seal it all up $4. Pipettes and or syringes for measuring $5 tops. Anything else you may want or need is probably laying around the house already, like 6 outlet power strips. Oh one more thing always act like you have bugs even if you don't see any. Keep some Neem oil around just in case $10 better to have it and not need it than to need it and not have it. A circulation fan you can grab at Home Depot for $15 each.
Budget for miscellaneous shit $115
Whole set up $902 to $1117
Yes there is a thousand ways to skin a cat! With all the member on this site you will see both cheaper and more expensive suggestions and you will see both better and worse suggestions. I don't know your budget or experience so I'm basing my opinion on what is working for me in my environment. I'm in the northern mid east, U.S.A.. I use LED so I don't get too hot in the summer but I plan to switch to a 400 or 600 watt MH/HPS for the winter so I don't have to add a heater to my grow room.
If you use 1.5 ounces a month then the cost is about $900 in 4 months at $150 an ounce. $1200 in 4 months at $200 an ounce, so your first crop will pay for itself and more. With the help of the good guys and girls on this forum you will get better every cycle and your yield and quality will improve every cycle. You will also feel better knowing what's in or on your medication
Just for giggles check out HTG Supply, for under $600 you can get this 3x3 tent kit CGK-HTGOLSGTK-B. This kit has most of what you need to get started. Light, tent, nutrients, soil, fan, ducting and more. My way is more customized to my personal taste with what I think is a better light and carbon filter/fan setup.
Searching this forum is free and you will find a lot of links for sites that teach you everything you need to know to be a better grower. growweedeasy.com is one of those places.
I hope I helped, good luck