Getting dialog state from another component

Question

I have a PCF which load few components in the same index.ts: main container, aside container and another one container where a dialog component is loaded. This dialog includes a dropdown control which load some items from the index.ts init procedure. Could I get selected values from another componets?

My index.ts:

public init(context: ComponentFramework.Context<IInputs>, notifyOutputChanged: () => void, state: ComponentFramework.Dictionary, container: HTMLDivElement) {
    this.container.appendChild(this.containerMain);
    this.container.appendChild(this.containerAside);
    this.container.appendChild(this.containerDialog);
    // actions to populate this.list with WebAPI.retrieveMultipleRecords
    ReactDOM.render(
        React.createElement(Dialog, Object.values(this.list)),
        containerDialog);
...   

public updateView(context: ComponentFramework.Context<IInputs>): void {
    ReactDOM.render(
        React.createElement(Main),
        this.containerMain);

    ReactDOM.render(
        React.createElement(Buttons),
        this.containerAside);

}

Dialog component is this Fluent UI component and must be opened at the component loading.

My question is, could I save the user's chooises from the dialog in order to modify other components with it?