How to check what is the problem of slow computer performance?

Question

Computers

Hello. Is it possible to somehow check why the brakes suddenly began to appear in the system? Or will I have to blindly reinstall the OS?
From the noticed:
- The browser starts slowly (Mozilla Firefox)
- Sometimes explorer.exe hangs
- Sometimes the image viewer hangs strongly
- Brakes while typing in Telegram Desktop
- Freezes in games

The configuration is as follows:
- Intel Core i7- 3770K CPU @ 3.50 GHz 3.50 GHz
-- 16 GB RAM (Crucial Ballistix)
-- Windows 10 Pro x64
-- ASUS GTX 1060 3GB
-- SSD 120 (like Kingston)