I honestly think the best thing to do is to take lessons, and ask your teacher if they have other students who'd like to play with you.

You can also go to jam sessions if you live in an area that has a good music scene; I live in SF and there are regular jam sessions for bluegrass/jazz/folk/country/blues nearby. But, the thing about jam sessions is that you have to be able to play at a certain level to really enjoy them.

I think honestly the best solution is one that almost no one takes: hire really good musicians to play with you. When I was in music school, I had a professor that would literally say: "For all the money y'all pay in tuition, you would play better if you took that money and hired $famous_drummer and $famous_bassist to come play trio with you at your house".

Obviously if you are a beginner you don't need to hire the best people in town, but most professional musicians in this day and age are going to be happy for a gig like this.