You can either upload images in Lightroom by importing them from a file on your computer, or you can set it up as an automatic program when you plug your camera or SD card into your computer. I like to do a preliminary run through of my photos and then tag the ones I will be importing into Lightroom to save space on my Adobe cloud.
There are hundreds of free presets available online. For many you must provide your email address to become a member of the site to receive the preset. If this is the case, you can always unsubscribe after you receive the preset, no sweat. The best place to find a conglomerate of free presets is by searching for them on Pinterest. I suggest getting about 25 that you actually like, ones that can be modified to make subtle changes to you photos instead of making them look like your first filtered photo on Instagram. Subtle is always better if you are using your photos commercially or personally.
Learn what level of exposure works best for your personal brand. Many times professional portraits will be slightly overexposed and adventure photography will be slightly underexposed to get more depth in the photo. This is an excellent time to learn how to use your tone graph on your upper right hand corner. the best light in photos always have a good balance, find yours.
This portion is home to the sharpening and softening tools. If you sharpen your photos, make sure to take a look with the zoom feature to see if you created any static. If you have, the luminance feature will soften that sound and improve your overall photo quality.
The dehaze effect is my favorite feature on Lightroom. This allows you to take overexposed and cloudy photos and make them look like they were taken in clear skies. This does wonders for sharpening your photo and adding detail lost in the original shot.
This is the easiest way to make your photos look professional. Learn how make your photo have the correct perspective horizontally and vertically, and always make sure everything is level in a straight line. Make sure the main focus of your photo is always centered and level.