I'm making my garage into a living place and I put in a 50 amp line from my house to the garage. The garage has its own fuse box but I want to have an upstairs living area and a downstairs man-cave. I want to plug in a freezer, refrigerator and a couple of AC's and of course upstairs would have a TV and a computer. Am I going to have enough amps or am I going to be blowing the fuse box often?
Look at the published ratings for each of the specific appliances you want to run simultaneously, and add them up. You'll have to do this yourself; we don't know which units you're interested in, and in fact it may affect which ones you purchase.
If the sum is more amps than the breaker will permit, the breaker or fuse will eventually blow when everything happens to make its peak demand simultaneously.
A 50A (@240v) feeder will be more than enough for this load. If this were a work shop where several larger tools would be run at the same time then you might be pushing it, but a few window A/C's and some electronics will be absolutely fine.
Remember, 50A @ 240V is 12,000 watts. A 10k BTU A/C is around 1000 watts.
The best way to find out is with a Kill-A-Watt or equivalent. They are sold at most big box, hardware stores, and anywhere electrical supplies are sold. I just bought one off Amazon a couple of weeks ago to see how much power some LED lights I bought will draw. If you want to watch your usage over time there are even many new products that will report via you house WiFi or Bluetooth.