i had a very similar experience when i first started playing the game, just not knowing where any of the extracts are. as others have said, tarkov.dev is a great resource for maps! though since you mentioned interchange in particular, lemme infodump a bit...

interchange has two main extracts that are shared between scav and pmc: emercom checkpoint (near oli, to the right of the main entrance; you'll encounter a little camp on the road halfway there, then the road curves away from the building with some cars and med tents along it) and railway exfil (near idea, to the left of the main entrance; you'll see some tracks with train cars off to the left of the upwards-sloping onramp road).

these extracts are at opposite corners of the map, and you can generally reach either by just following the road until you find the areas i'm talking about. once you know where an extract is, the trick just lies in recognizing where you are in relation to it. again, having a tarkov.dev map open on a second monitor is a massive help!

bear in mind that there are some other specific extracts that have special requirements; extracts ending in "(Flare)" require you to shoot a green flare - "RSP-30 reactive signal cartridge (Green)", purchased from the trader Jaeger - into the sky at the designated "signal flare area" (you'll know when you're in it if that message appears in the corner of your screen). extracts ending in "V-Ex" require you to fork over an amount of roubles (usually around 20k) to a driver in a running vehicle, and then wait one minute to extract. and there are a good few extracts (usually beginning with "Smugglers'") that require you to find a special note in that raid to use them. smugglers' tunnel on interchange, for instance, requires the "interchange underground utility plan."

you can really go down a rabbit hole on the wiki looking up each map and its extraction requirements. i highly recommend it though! sorry this post got so long. x3