Right click your task bar and select task manager, check to see if anything like cpu or ram is stuck at 100% (or even hitting 100% occasionally), if it is then you need to upgrade that part since your computer is having to wait to process the new data that it needs to stream which will cause your stream to freeze up while it's waiting for the new data. If it shows the network hitting 100% then you need to increase your bandwidth, if your streaming with Wifi you can increase your bandwidth by switch over to an ethernet cable and try again, if your still having issues then I would contact your ISP and see if you are able to upgrade your internet package. If you wanted to test a higher bandwidth connection (like what you would be asking your ISP for) before you commit to upgrading, you can set your phone (if it has 3g or LTE or even 5g) to act as a router, connect to that wifi hostspot and try again, it's not ideal as your still capped by the limits of wifi but it should give you an idea of where the problem actually is.
