Eliminate these steps of configuration by integrating Magento 2 Ajax Search extension in your Magento 2 Store.
Steps to Configure Search Catalog Search in Magento 2:
Step 1: Navigate to Stores>Settings>Configuration
Step 2: Click on Catalog>Catalog.
Step 3: Explore the catalog section and follow the below instruction
Minimal Query Length field: Add the number for setting up minimum characters that can be permitted in a single query.
for more: https://magecomp.com/blog/configure-search-catalog-search-magento-2/