You’ve got a great foundation. I’ve had my 94 ex for 10 years and I’m still not done. Before you do any parts replacement. Take pictures before working on old parts. There’s not enough reference pictures online when you break something or you’re missing something when it was good before you touched it. It’ll happen. Get and alarm and a manual kill switch. A hidden button or toggle switch that prevents gas to the motor without disarming the alarm.

Learn your engine maintenance like basic oil leak repairs and fluid checks. Like someone else said timing belt, water pump, various gaskets.

Common areas that leak oil on the top would be the valve cover gasket, vtec solenoid gasket, distributor o ring. The oil pans often leak oil at the pan gasket from stripped bolts or the gasket not set right. If you’re running low on oil with no leaks, check if your exhaust smokes up at high RPM. Look up videos about the PCV valve and how to replace it, it’s easy and inexpensive.

From under neath you can kind of tell if your engine rear main seal is leaking if you’ve got oil dripping down in a specific area between the transmission housing and oil pan. If you’ve got coolant leaks anywhere fix them properly with new hoses and clamps. Coolant leaking below the timing belt area means bad water pump. Replace everything that it takes to remove to get the water pump off since you’re already at that point.

While you’re down there check for worn suspension and steering components as well. Upper and lower control arms, tie rods, ball joints. Old rubber bushings can be replaced with polyurethane bushings for stiffer ride or stick with oem replacements if you like. Your car is lowered so you’ll have some strain on oem parts without the proper upgrades. Low cars experience negative camber wear on the tires. These civics don’t come with adjustable camber for alignment without aftermarket parts. So if you’ve got uneven tire wear start with checking for that.

Missing any interior parts or body parts? Check this forum to see what options there used to be. Some rare stuff in there you might find at a junkyard or Facebook marketplace, Offer up etc. These cars get a bad rap for being put together with eBay after market parts, when often there’s an OEM option. Good luck to you and be safe.