No worries! That is one part of my life I do not miss...
Hang in there!
For lighting, I generally recommend as many lumens (video light)/as high of a guide number (strobes) as you can afford as light seems to fall off much sooner underwater. It's always nice to have the light available if you need it or you can turn it down if you don't, rather than not have it if you want/need it.
If you are doing video, you will want at least 1 strong video light (so look for lights that are not spot or those marketed for video). I suggest starting at 3500-4000 lumens. You might already have a dive light that could work so check before buying. I'm not sure how all-in you want to go from the get-go but you can get your camera rig in pieces; if that is your plan, I suggest getting lighting before getting a wide angle lens but if you're jumping in all at once, factor in the hardware (tray, arms for the strobe, the shoe mount or triple clamp for your video light) as well as the floats into your budget as it adds up! When you look at the hardware, flex arms will always be less expensive and will be convenient but do note these are more difficult to adjust on the fly underwater to get the necessary angles you want and they are less futureproof than ball mounts/arms/clamps which let you change up the length and add/remove components and accessories along the length of it. To prevent loss and to lasso your rig in, I highly recommend the Cetacea CRL-11 coil lanyard. It is excellent and will work well for you on deco stops; you can clip the entire thing to a d-ring and during your stop, you can buckle it onto itself so that its against your body.
I suggest looking at strobes from Inon such as the S2000 or the Sea and Sea YS-01. Both have manual mode and are more future proof and I think manual mode comes in handy as it gives you more lighting and exposure options when you don't have full manual mode on the camera. Some folks have gotten frustrated when they are relying purely on camera settings and TTL (no manual on the strobe).
I know it's super overwhelming but if you can get yourself to an underwater photography store or reach out to one, it will really help. I was so overwhelmed when I was purchasing my setup and I found it really helpful to speak with others who had already been through the process so that I don't get the salesman's pitch and found an honest shop that kept my needs in mind.