They sell portable wifi hotspots for a monthly price, It is a physical item you carry around. The only downside is it is dependent on cell towers. So if you have a weak connection it might not be a viable solution.
Just google portable wifi hotspot to learn more.
Another solution would be to get a data plan from your cell provider so you can get online. Which again is dependent on cell towers.
Lastly, If you have a Comcast account and there is an xfinity hotspot, You can connect to it by logging in with your Comcast credentials. Most businesses with Comcast internet will have this and you have probably seen them a thousand times and never knew.
These are the only 3 alternatives I can think of.
Use your phone's cellular data.
You need your employers permission to connect to their wifi.
You should be working not using your phone at work.
You should not connect anything to your company secured network without permission if you value your job. Besides that, it might block whatever you are trying to do if it is something on the Internet that can only be accessed through a company web proxy.
Simply use your mobile data. That way they cannot see what you are doing.
No, you can't get wifi like that. You have to use your actual phone connection and pay for the data.