I'm new to Backpacking- looking for an intro class or intro trip in the DC Virginia area.
Hi @lnl555 ! My turn to join the party. I see a lot of good advice in here about specific product recommendations already, but wanted to share a few other thoughts. One of the most important things to consider with your pack, other than capacity, is the fit and comfort. If it's not comfortable on your back, it can ruin your whole trip. Personally, I really like a suspended mesh back-panel. It may prove to be a little heavier, but the added airflow can be a godsend. Not to mention that what sweat does develop on your back won't transfer into the pack or contents.
As for tents, I agree with @nathanu and @bryndsharp that a 2-person tent is preferable. Especially if you have to wait out a rainstorm. You can keep you and your gear dry without feeling claustrophobic.
REI is a great resource to "book learn" about backpacking and camping, but nothing prepares you like real-world experience, so, after you get your supplies, make some day trips carrying your whole load. Practice in your back yard. Take a few weekenders to get used to unpacking, setting up camp, and tearing down and re-packing in the field before you try anything extended.
And, for places to go, I live in Central Maryland, and have found the DNR website useful. https://dnr.maryland.gov/Pages/default.aspx
There aren't many back-country or wilderness sites until you get to Western Maryland, which is about 2-3 hours from the DC area. Savage River State Forest is a good spot.
Hope this helps. Enjoy!
Another thing I would make sure to do prior to backpacking is to receive some amount of wilderness first aid training. You do not want to be stuck in the backcountry with a medical problem and with absolutely no idea of what to do.
I have participated in both the Wilderness First Aid and Wilderness First Responder courses and earned the subsequent certifications from NOLS, and would highly recommend their institution. For your situation, the basic Wilderness First Aid training should suffice, but if you are looking for something more in-depth, then go with the Wilderness First Responder course.
While there is much great advice here, I would stick to what you can reasonably afford. REI and many other companies have fantastic gear, but sometimes at a a premium. I would focus on a good tent, sleeping system, and backpack (last). Get an REI membership so that you can earn a dividend on what you buy there.
For hiking/backpacking, the Shenandoah National Park (about 2 to 3 hours from DC) has really great backpacking and hiking trails. I would look there as well. There are plenty of both free and paid camp sites that are available.
If you are looking to not solo, drop me a line. I'm always looking for a new adventurer!