Hosting a game as GM and others behind one computer on different location.

Hi, new guy here. Our small band of friends has been playing RuneQuest, Cthulhu etc. since 1993 and first time we have a situation that we can't play at the same location due to this covid situation. So long story short, is it painful or manageable to run a game while others are on the same computer on other location and GM being at the other end? I'm the GM for the group so trying to find information whether Roll20 is the best fit for this kind of scenario? 

You could definitely do this with Roll20.  The main thing is that you won't be able to separate out different character's vision to each individual player, but if you've been playing in person then likely all players could see the entire game board anyways, so that won't change much for you.   Even when all players are playing in the same location, it's generally recommended to have a GM screen/computer that is separate from the player's screen, so that you can see anything that is hidden from the players until you want to reveal it.

This is possible, with a few Caveats.  1. You cannot use player Character Sheets in Roll20 in this scenario, as they would take up too much of the screen and be difficult to use . Have them use Paper Sheets, you'll just have to trust them with rolls etc. 2. Make sure they have a VERY good mic on their end. I'm talking a $100+ Omnidirectional Mic, like a Blue Snowball. You do NOT want them relying on any microphone that can't capture all of their voices while not blowing your eardrums out. 3. They need a wireless mouse to pass around so they can move their own tokens if need be when its their turn. If you want them all to be able to do it at once, four mice. 4. It goes without saying, but make sure they have a big screen.

I think Character Sheets will be fine, just make judicious use of minimizing them with a double click on the title. There are some API Scripts that can make this easier (API is a Pro Subscriber Perk) as well.  (I'm thinking of Observer here)

And very soon™, there will be a mobile app that will let each player make rolls from a simplified mobile sheet.

Okay sounds good. Our game time has been always relying on story telling on the fly and everyone can see the big picture so it sounds like it is doable. I think Roll20 might just add more to the fun with better fog or war.  Have to make sure they have a Jabra ready and use that bigger screen on the other end, Check. And most likely there won't be any problems with paper character sheets since part of the fun has always been the big fumbles :) I can be sure my friends are very keen on seeing that everything goes by the book as it is about having fun. Some player characters are already 15 years old for the same Runequest campaign.