I have seen a tennis coach twice a week for the last few months, and I cannot suggest it enough. Many people have been flirting with tennis, and you can see improvements on your own, but the foundation needs to be set by someone who knows more than you. The repetition, notes on form, and endless drills work in a way that watching Youtube videos just doesn't. It also creates some accountability, and if you are spending the time and money, you will feel more inclined to leave it all on the court.