Just had a heavy Weber 1200 shipped to me only to discover it doesn‘t connect to my gas cylinder. Any idea how I can connect them is very appreciated. Below are picture of Weber inlet, and my gas cylinder.
https://twitter.com/fahad77806521/status/1266754074323664897?s=21
I think those grills were made to run off a small propane bottle directly attached. Hardware stores and big box stores like Home Depot carry hoses to connect larger tanks but I’m not recognizing the connector on your tank, it looks like a natural gas fitting that may require another adapter to connect to standard hoses.
It’s designed to use a disposable propane cylinder. But I believe they make a coupling that will allow you to use a standard propane tank.
It’s main design is for it to be used as a portable grill. That being said they also make a fitting that allows you to refill the smaller tank using the standard propane tank.
Search for “bulk tank adapter” 
Get one of the ‘small propane bottles’ that this was designed for. (Specific examples should be listed in the grills’ manual.) Then take that with you to the hardware store and tell them you need the adapter to connect to a big gas cylinder instead of the small propane bottle.
Every time I’ve had to do something like this, the store staff is really glad that I have brought the pieces in, and provided them with all the info they needed – much better than having to guess when a clueless customer describes the doohickey connecting to the thingamajig that he needs. They are always happy to help, and even if I feel foolish dragging dirty parts into the store, what they get me works, with only one trip to the hardware store!
You want a 1 lb to 20 lb propane converter. It works with Weber Q grills. The official ones on Amazon are $35 ish, off brand $13 or so.
@The Sheikh
Where are you located? In Canada and North America, screw-in propane cylinders are the norm but not elsewhere. I’ve only ever seen that style of tank / adapter (on the left in the twitter photo) outside of N.A.
If you’re not near an HD or other DIY store, then the company that provides you your propane should be able to provide you with a new regulator that matches the style of propane tanks they sell in your area. When I was in Asia the company I dealt with provided it for free when I bought the tank.