Hi bro, welcome to this hobby. My comment is as follows;
Tank, pl light and canister filter can be reused but yr pl light might need to chge bulb if u intend to keep corals or bring out the luminous effect of yr fishes. The core things u need are rock(live or dead) and seawater(self mix or buy seawater). U may choose sandless. Equipment wise, u need to have circulation in the tank and this can be achieved via wavemaker or powerhead(can be done but not ideal). For filter,u can use sump&overflow method or canister. For canister, u need to be hardworking to wash the medias, etc. Overflow(external or internal) with sump may be easier to do maintenance. For chiller, not a must but depending on yr livestock requirement. Some ppl will use fan as replacement but it will cause high evaporation and u will need auto or manual water top up. For biological filter, u can use a few methods such as algae scrubber, deep sand bed(magic mud, etc), refugium, mangrove, biohome(bacteria house, etc), dosing bacteria, etc. Just for yr info, skimmer is not a must but recommended. Hope my comments help.