OK, a quick primer - and nothing against Bay Photo but they are in California and I am in Florida so have to think about shipping/client delivery times.
Paper - many times will also be expressed in grams noting the density/weight, but two different technologies - wet and dry. Most straight prints (low price leaders) from both professional and consumer labs are wet based, silver based darkroom chemical processed prints, and may refer to paper as e-surface or or something. Of course, they are available in various textures - glossy, matte, etc...but (hint) you will never find the paper available at B&H or other sources to purchase (might be in a different section with darkroom chemicals where I know the keep B&W papers). The "darkroom" are those gigantic machines you would see in Costco, Walgreens, etc and watch the fully processed print emerge for cutting and packaging.
Dry Paper - You can purchase these and intended for ink-jet printers. Among professional, and perhaps consumer, printer they may list under the category of "Fine Arts" archival prints or Giclée which translation literally means the spraying (of ink). Two types of ink - dye based (90% of all inkjet printers) and pigment based ink (high end printer) which is rated to have greater archival values assuming all are printed on acid free papers. While both wet and dry are good, the dry is considered wo give greater detail as the have from 8 to 12 cartridges to mix for more color combinations as it precisely sprays the ink.
Canvas - This will be dry method. The big issue is on sizing as it has to do with the 3/4 to 1.5" wrap- and they will give instructions. Two methods - solid border, typically choice of black or white, that showed 100% pf picture on surface. The other choice is edges of the photo wrap around so the display surface is essentially cropped to accommodate the wrap. Those are thing you have to be aware of. I have done a variation of that in Photoshop selecting a wrap strip, moving and flipping a mirror image of the edge to accommodate the wrap and show 100% on surface. I also let the printer know what I did so they don't try to correct.
Labs - really any of them. It may be because I signed up with WHCC as a professional for my website store but they sent me a sample pack to view papers and textures. Take advantage of a sample pack if they offer it. With local labs using darkroom processing - like Costco use to offer in their store - I would drop off (or upload from home) early in the day to get the freshest chemicals. Not that critical with inkjets. With the national labs don't be intimidated that their marketing push is for the high volume photographer - schools, wedding, events, etc as they do small custom jobs. I found it interesting that their default paper was wet based which notes their processing. The one exception I noted was Adorama's Printique as the only noted using Hahnemühle inkjet paper with no reference to other papers. While I use WHCC only because web store hosting, Pixpa didn't offer a choice, my first choice would have been Mpix (or their professional division, Millers) and Bay Photo - except for the distance. If I didn't have a local lab, Printique would definitely be in the mix. The more consumer focused labs like Smugmugg, Costco, WalMart, Walgreens etc, are OK except 1) the professional focused labs are price competitive, and 2) 100% of their business where employees are trained and may do color and print analysis as part of the service that would not anticipate at the consumer level.