Hello @Paul_Silkiner1 and welcome to the forum.
Yes Roon will resume the scanning after a restart of the software.
Note: Your Roon Core software needs to be running for the scanning to happen. As you did not give detailed information about your setup (what you use as Core) this is all I can tell you. Please follow the information given in I’m having a problem with Roon – how do I report it? next time if you need assistance.