gobiggergoredder

Second the buy something cheap & see if you want to stick with it idea. But first hit up a bike shop or two and try a few different bikes. Get a feel for what types of bikes are out there, and what size you need. Then hit up Craigslist or Facebook Marketplace for something cheap that fits your basic wants. If you stick with it, you can get something nicer down the road.

Great advice.   Go cheap with your first bike purchase.

Check bike store bulletin boards, eBay, etc. for good less expensive  bikes. If you have any friends who cycle, take a spin on theirs to see how you like it. 

Fit is the most important point in my opinion because if your bike doesn’t fit you, you will be miserable and stop trying!