There are kits you can get at your local nursery.
You can buy the soil testers on Amazon.
There are soil testing kits available at almost every Hardware Stores & most Garden Centers. If you live in a state that has a lot of Agriculture, the State University will have University Extension Offices that have Soil & Garden experts who will suggest how best to test & amend your soil. Give them a call, even if they're not in your community.
Perform an informal test: You can determine whether your soil is alkaline or acidic using simple white vinegar. Just put a cup of your soil into a plastic or glass container and pour white vinegar over it.
If the soil bubbles up, you know that it is alkaline. The more vigorous the bubbling, the more alkaline the soil. If no bubbles appear, you know that your soil is acidic.
Soil tests are always recommended every few years. Most every speaker in my master gardeners class recommend this for optimal way to address your soil and circumstances. The box and instructions can be obtained from your local cooperative extension, unless you want your lawn service to do it.
You have to have a good soil to meet your needs to growing grass. From there you will find out recommendations to promote the grass growing conditions to include fertilize lime ( pH adjustment) aerate and seed.