How to deploy developed scripts?

When I finish my development part , how can I deploy my work ?
How many robots can I use to run simultaneously?

You can publish them to Control Tower and and schedule to run at certain time.
You can read the details here: https://kb.workfusion.com/display/RPAe/Control+Tower

In the free version, you get 1 bot running simultaneously. In the Pro Subscription, you get multiple bots.