All depends on what way u want to go about it. Low techs can be very different and have many different methods.
I'll start with substrate, u have the choice between a nutrient rich substrate like soil, Ada soil, Tropica, flourite, stratum etc or a substrate that holds nutrients from the water column like Eco complete.
Any sand is fine or any normal gravel is fine. U can use root tabs to help fertilise plants at the roots in substrates like these.
A lot of low tech plants do better tied to driftwood or rocks. Java ferns of all types, mosses, anubias can all be tied or glued to the wood/rock so has no need for a nutrient rich substrate.
Crypts, bacopa, Amazon swords, buce, vals will all benefit from nutrients in the substrate but it is not a necessity.
Driftwood and rocks are a great addition to a low tech due to being able to attach the plants to them. Ferns and moss attached to wood can really make a nice scape.
Lighting: depends on the tank size and depth. If u want to go with fluro's over LED's then go for 1 or 2 t5 6500k bulbs.
If you prefer LED's then something dimmable like a finnex planted plus or a chihiros A serious is a good way to go. These lights are quiet strong so I'd be running them at level 1-2.
Beamworks is a cheaper option again but make sure u get a dimmable one.
Ferts: once again u have a few options. You can dose PPS pro dry salts (can be brought online) or EI with the same salts.
If this seems all abit confusing and u would prefer premixed off the shelf products then go with the seachem range (flourish,flourish excel,trace,iron) or thrive+ from nilcoG (an all in 1 fertiliser)
Dry salts are cheaper especially if u have a larger tank.
Filtration: general rule is 8-10x tank turn over per hour. Either with a HOB (hang on back) or a canister filter. Both are good but I prefer a canister with a spray bar.
Low tech plants: just google the first word and "species" to get images and info.
Crypts of all varietys
Vals of all varietys
Hygrophila' of most varietys
Buce
Bacopa
Java ferns of all types
Mosses of all types.
Good low tech carpets can be made from
Crypt parva and dwarf sag.
I'll post a few links that may help in the edit.
EI fert dosing:
http://www.aquaticplantcentral.com/...-index-dosing-guide.html#/topics/15225?page=1
PPS pro fert dosing:
https://sites.google.com/site/aquaticplantfertilizer/home/pps-pro
NilcoG thrive+
http://nilocg.com/thrive
Lights:
Finnex:
https://www.ebay.com.au/ulk/itm/122237146406
Chihiros:
https://www.ebay.com.au/ulk/itm/322355624931