The simplest option is to use a faucet-mounted filter that screws directly onto the outlet of your current faucet, without touching the pipes. These filters almost never require tools or special knowledge. You just need to turn off the water, unscrew the aerator (that small piece at the tip of the faucet), clean it a bit so there's no dirt, and then screw the filter in its place. It takes five minutes max and there's no risk of damaging old pipes because you're not touching anything under the sink.
If you prefer a filter that goes under the sink, then there's a bit more complexity. You'd need to cut a small section of the inlet pipe, install two connectors (which are held with plastic nuts that are easy to tighten by hand, no force needed), and then the filter cartridge. This isn't dangerous either if the pipes are plastic or modern copper, though it's true that if they're really old or corroded, working on them can release rust or break something. In that case, I'd say call someone.
About the yellowish color you mentioned - before you install anything, check whether the problem is coming from your house or the municipal water system. If it's only happening in the kitchen and not in other faucets, it's probably sediment in old pipes, and a filter will help. But if it's happening throughout the house, it could be something more serious. Either way, with a faucet filter you've got nothing to lose trying.