Love to come over to help but live a little far away. If you're starting from product knowledge zero just tackle one job at a time. Buy/borrow tools as you need them. The labour you would spend on a mechanic buys a lot of tools. Tool kits with many tools are good buys from low cost dealers. Get book like official manual (jclay has it on his website in pdf.) Get cheap digital camera with macro and take lots of pictures as you take things apart (step by step). You can just reverse the steps (pictures) as you put things back together. (cheap laptop is handy to have nearby for this). You will not remember so don't even think of doing it from memory.
Initially change all fluids. Oil, coolant, gear case (ATF or Synthetic), top up differential. Rubber deteriorates over time so rebuild clutch, brake cylinders and if water in fluid of these systems has corroded them replace as a rebuild then won't last. Methodically clean every electrical contact, dielectrical grease on them to get rid of any electrical gremlins. Under dash stuff is a bigger job because it is done in one foul swoop as opposed to bit by bit as the other areas can be done. That looks after important areas of shifting, braking and electrical gremlins.
If engine isn't running right, check/replace spark plugs, S/P wires, dist. cap, points, intake vacuum leaks, carb rebuild?
Handling: Check/replace shocks, rubber suspension parts, (gaitors, stops, bushings) springs can sag, replace rubber suspension parts with poly for long term and to tighten up suspension including steering shaft bushing if worn or missing. Grease steering rack.
A garage is nice, (working in the cold and rain is not fun) or you'll be working in the summer (good driving weather).
Derust body parts (wire brush and/or POR-15 metalready or the like) prime and paint or POR-15 and paint to stop rust cleaned areas before they get worse. If it goes through body panels, sections have to be cut out and weld in replacements. This requires a different area of expertise. The previous stuff is engineering that latter is an art.
Learning how to do is one of the many pleasures of owning a TR7 (or any older car). This rambling is only an over view of course but may give some idea of where to start. Are there local club/chapters of Triumph or English cars in general in you area you can join? These usually are full of guys who have a lot of general and specific knowledge and may be your best bet.
TR7 Spider - 1978 Spifire - 1976 Spitfire - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra
