assigning dynamically values of string array to properties of an object in typescript

suppose a component named searchBox receives tow inputs: @Input() titles: string[] and @Input() model: Object, that the number of titles values is equal to number of model properties. searchBox generates input box to number of titles length, and gets searching subjects from user and push them into a string array named titlesValues. so, searchBox should assigns the values of titlesValues to model properties peer to peer and outputs the model via @Output resultModel: Object. I tried to access each model property dynamically for assigning to, therefore I encoded this scenario in the following:

let i =0;
  Object.keys(this.model).forEach((key) => {
     this.model[key] = this.titlesValues[i];
   });

although I tested much statements and alternative codes to get desire result, but it gets bellow error:

Element implicitly has an ‘any’ type because expression of type ‘string’ can’t be used to index type ‘Object’.

how can I implement this scenario?
Best regards.