All you have to do to know where to start " in order" is to look long and hard at that pic that you just posted.
The car needs wheels and tires, and that vert back window replaced. Then it needs about ten dollars worth of quarters at the pressure wash, and wash off that peeling plastidip.
There is no sense in you spending one dime on "go fast" junk until you can actually get it to " go reliably". If it was so badly neglected, that it looks like this on the outside, you need to cover the safety issues first. Stock brakes are cheap, and as opposed to driving on some marginal pad thickness in anticipation of a 4wheel disc conversion, warranted.
Why you'd even take it around the block on a mini spare has me scratching my head. Put tires on the thing.
Shocks, struts, steering, brakes, bushings fluids, battery, charging, starter. Once all of that checks out, then start worrying about going faster.