Google Ads is a broader advertising platform where you can bid on keywords, target many campaign types, and usually pay per click or conversion depending on the campaign model. Local Services Ads are a lead-based format designed for local service businesses, and you typically pay per lead instead of per click.
LSAs also rely more on service area, verification, and lead eligibility, while standard Google Ads gives you much more control over keywords, creative, audiences, and landing pages.
To know in detail: Google Ads vs Google Local Services Ads: The Technical Difference Most Businesses Never Understand