Google Sheets Multi-Dropdown Function

I'm seeking a skilled app script professional to improve functionality in my current Google Sheets. The job entails creating connections with external APIs, and add a multiple drop down function in Google sheet. This is different than dependent drop-down and I require to use just one cell for the multiple drop down rather than using the next cell.

Key requirements:
- Add two dropdown menus
- The menus need to feature a predefined list of words
- Experience with Google Sheets and App Script

Recommended skills:
- Google Sheets
- Google App Script
- API Integration