A bit of sage advice...from someone who 4 stepped his way to a good set up. If you're gonna do this, do it right from the beginning. Do not half step anything. You will save yourself money in the long run. Spend now, save later. I have a closet full of half step lights and gear. I wish someone would have told me what I'm telling you when started.

For 4 Plants I would suggest a 4x4 (minimum) Gorilla Grow tent:
https://www.amazon.com/Gorilla-Grow-Tent-4-4-Feet/dp/B00KCSSBWY/ref=sr_1_5?dchild=1&keywords=Gorilla+Grow+tent+4x4&qid=1621371803&sr=8-5

To light that space you'll need max of 1040 PPFD ( µmol ). So I think you have some options in the latest Quantum Board LED's. Do NOT get any type of blurple light bullshit. DO NOT. Good light options: HLG, MarsHydro , SpiderFarmer etc.

Fantastic Light for a 4x4 with room to grow into a 5x5. HLG 600 Rspec is great for the full cycle of grow.

https://www.amazon.com/Horticulture-Lighting-Group-Certified-Inventronics/dp/B08JP7694C/ref=sr_1_10?dchild=1&keywords=hlg+550+v2&qid=1621372371&sr=8-10

PH Pen. MUST HAVE. Do NOT skimp on this. This is pricey but it's awesome and you can replace the head. https://www.amazon.com/Apera-Instruments-AI311-Replaceable-2-00-16-00/dp/B01ENFOIQE/ref=sr_1_1_sspa?crid=3AKN7HNLXNE1V&dchild=1&keywords=apera+ph+meter&qid=1621372495&sprefix=Apera+PH%2Caps%2C173&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyTklLNlRGQzNOS0NOJmVuY3J5cHRlZElkPUEwNjk0MDM4M0JKV0lBRksxNEQ0OCZlbmNyeXB0ZWRBZElkPUEwMDI1NjQ1MTNQOUhROUZES1JFVCZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

PPM Meter (Yes, you need it) :https://www.amazon.com/Lxuemlu-Professional-Temperature-0-9999ppm-Aquariums/dp/B079DN9DRS/ref=sr_1_4?crid=1O00B34SNEOME&dchild=1&keywords=ppm+meter&qid=1621372562&sprefix=PPM+Meter%2Caps%2C166&sr=8-4

You'll need Fans, humidifiers, dehumidifiers, space heaters and air conditioning.

Get good soil and cut it with 30% Perlite for aeration.

Use cloth bags, or preferably, rain science bags: https://rainsciencegrowbags.com

Nutrients. Organic? Bottled? Dry Amend? SOOOOOOOO many ways to feed. I like MegaCrop by greenleaf nutrients

It's a lot. I know. I'm here to help and answer your questions. DM if easier.