Support for Field and Boost at Query Time

Now that Index time indexing is deprecated I'm trying to move to query time boosting but I'm not able to properly build an query.

The issue is that my query is dynamically built and I have a list of individual fields and their boost values. For example

Name : Boost 10f
Legal Name: Boost 1.5f
Description: Boost 0f

I have a class below which I use to store field name and boost value

What is really need is to be able to loop through my fields that I want to query and their boost value like below

I cannot however find a way to add individual fields to query each with independent query values.

Something like the below.