Planning on buying a BRZ, have been struggling to find out how to upgrade it

I've been watching a lot of videos on DIY work for installing parts or anything in general and it all looks very overwhelming to me. Eventually I'd ease into doing it all myself but for initial upgrades like tires/wheels, air intake, exhaust system, exterior bodywork, etc, how do I go about getting all of this done? I've asked friends and there's an option of paying professionals an hourly labor rate to do all of this for me if I bring the parts but I just want confirmation or to be corrected. Thanks in advance for answering.