Laravel PHP Function

I need help building a function in my Laravel web application.

I have 2 tables in my database ('Accounts' and 'Customers') with the following columns/fields (see database structure screenshot).

The 'Customers' are related to accounts by the 'accountid' field. For example; Account could be Microsoft and Bill Gates would be the Customer related to that Account. So on the Bill Gates Customer record, it would have the 'accountid' that corresponds to the account ID of the Microsoft account.

I need to build a function that allows the user to search for an account in the database when they are creating a new customer record. I have the Customer record create form page completed and working but I'm struggling with the function to allow the user to be able to search for the Account when they are on this form. Also, if the Account does not exist in the database already, they would need the option to be able to create a new Account. The create customer form will need to remain intact when the user is searching for the account so they don't have to enter the information twice. Once the Account is added to the create customer form, the user would then be able to save the record.

I have attached a video of an example of how a very similar function to what I'm trying to create is done in another 3rd party application. I would like something very similar to this in my application (possibly using modals to achieve this). Please ignore the extra fields on the video, this project/task I'm asking for is just for the creation of the lookup/create an Account function.

I will likely have more work in the future for the person who can help me with this.