An Azure machine learning service for building and deploying models.
Azure services have different charging models.
It's important to understand what services you have deployed, if their costs are static or if they fluctuate based on usage.
Generally speaking, yes - deleting resources will lower your Azure spend. However some Azure resources are free, and some have a free tier.
Azure Cost Management provides views into your spending, which you can use to investigate which services/resource-groups are costing your the most; https://learn.microsoft.com/en-us/azure/cost-management-billing/costs/quick-acm-cost-analysis#analyze-costs-with-smart-views