Thank you all who are helping to agree that it is OK to use all best knowledge, and technology we have for safe navigation. Most of time as beginner I am staying very close to visual reference of known land. Due to lot of factors this can be confusing.
Especially when judging distances over water. In this case charts, and last known position on it clears confusion between visual reference, and what chart plotter is showing. Practice, practice, and enjoy doing it especially in fair weather, as they say.
You're right Osprey. It's all good. I think it really falls back to personal preference. I like being able to look at a chart and letting my eye pick out the details I need at the moment from within the big picture. Chartplotters get expensive as the size of the screen goes up. For me, even the big ones I've seen lose the fine details if you zoom out, leaving you the choice of looking at either the big picture OR displaying the details, but not both. Some people may be able to get what they need off of those small screens but not me. I just prefer a chart.
My sailing was done on Kentucky lake and at no time was I out of sight of land. I carried my handheld Garmin GPS but did practically all navigation with my chartbook, a compass, and my eye. The GPS came in handy at night or during foggy conditions. I wouldn't want to be without either.
If you don't deal with measurements on a daily basis, I would suggest getting a cheap rangefinder. They are pretty accurate out to 500 to 800 yards on a reflective surface. Once you get good at judging distance out to 100 yards you can use simple addition to count how many 100 yd increments are between you and your target. If you keep an accurate position of your boat, just pay attention to how far an object appears to your eye, then measure it on your chart. After some time, your eye will become more accurate. Hope that helps.