what is the max conventional loan limit, before I have to apply under Jumbo mortgage?

In your county, it's $765,600.00 for 1 unit properties such as Single family homes, condos, townhouses, etc. The limit is higher for 2-4 unit properties.

Depends on there the property is located. Pretty much currently $510,400 in most of the country for a single family home, and can be higher in "high cost" areas, and on multi-family properties. You can look up loan limits at https://joemetzler.com/mortgage-loan-limits-lookup/