You can use the Open Broadcaster Software, https://obsproject.com/
It is an open source software that allows you to record/stream anything on your pc.
Download the correct version for your pc (Windows/macOS).
On first opening, the software will ask if you want to do the wizard set-up. Click yes to decide whether to focus on recording or streaming, 30-60 FPS, the resolution etc.
Once you’re done with the settings, go to Source, right click, add –> game capture, select create new and click Ok.
Now select Mode, Capture Specific Window. In Window, select Vainglory (the game must be open), click Ok (unless you want to change the other settings).
Right click on the video, click Resize output (Source size).
Now all you need to do is click on start streaming or start recording in the bottom right menu.
If you want to stream click setting on the same menu, then stream and set-up a twitch/youtube/facebook/whatever you prefer account first. To do the set-up, usually you’ll need a stream key. Search on the internet how to get it (it depends on the platform you want to stream to).
You can find more detailed guides on the internet if you want to know about all the settings of OBS or specific stream services that are not included in the menu. This is just the most basic set-up to get things running.
For windows 10 you can also use the built-in record feature. Click Windows+G to open the Xbox Game Bar. Click on “Capture” to show the Capture menu. From there you can take screenshots, record last 30 seconds, start recording, turn mic while recording.
This won’t allow you to stream though.
You can use the google play games gaming screen recording built in
most devices, you can read the details on how to use it here: https://support.google.com/googleplay/answer/6274965?hl=en
You can also directly upload the video to youtube from the same app.
Another possibility is to use the Mobcrush app https://play.google.com/store/apps/details?id=com.mobcrush.mobcrush&hl=en_US
This app will allow you to stream to Mobcrush, Facebook, Youtube, Twitch and other services.
You can also download a screen recorder app from the play store, such as AZ Screenrecorder or whatever you prefer.
Go into profile (where you can see your level, the level chests, and in the other windows your skill tier for 5v5 and 3v3), below the Log-out button you can see a Record/Stream button (if you don’t see it, try to restart the app or open/close your profile). Click it, it’ll ask you whether you want to stream or record. Select your option. If you want to record, a small menu with buttons to start the record/stop, enable the front-camera or the microphone will appear. You can collapse the 3 buttons by clicking on the bigger one.
If you want to stream, it’s the same, but once you start it, it’ll ask you to “Find Live Streaming Apps”, such as Mobcrush. You’ll need to download and register to one of these services/apps to start the stream.