You cannot make purchases directly on a PC, but you can interact with the store in several ways:
1. Web Browser (store.playstation.com)
Browse games, DLC, view wishlist, purchase history.
Purchases require “Add to Cart” → “Proceed to Checkout” → you’re redirected to sign in on a PlayStation console or the PlayStation App to complete payment.
2. PlayStation Remote Play (PC/Mac)
Stream your PS4/PS5 screen to PC; navigate the store on the console remotely.
Requires console on same network (or internet with good upload) and Remote Play app.
3. PlayStation App (iOS/Android)
Full purchasing capability; push-to-console download queue.
4. Third-Party Price Trackers
Sites like PSDeals, Deku Deals, or Octopus Game Tracker show prices, history, and alerts – but redirect to official store for purchase.
Bottom line: PC browser = browsing only; actual purchase needs a console or the mobile app.