The entry door is timber, pretty old (classic), it lasted pretty well for the past few years. It's facing west so received a lot of love from nature (UV, heat, wind & rain, etc.). It's time for a rejuvenation.
Goal is to make it look lighter (less dark) so as to have a more contemporary look (instead of classic).
I have cordless sanders, what product (timber oil - varnish / taint) should I use to get that effect?
Also, what is the proper process to carry out this job?
Once you've sanded all the stain back so raw timber is exposed, you'll then be able to determine what oil or varnish or stain you'll need to use to achieve your desired result. If you were to use Cabot's exterior varnish stain, you can then use their colour visualiser and input the type of timber your door is made from to get an idea of what the stain will look like. As a rule, a stain will always make the raw timber darker.
You might like to post some inspiration pictures of your idea of a "more contemporary look" so we have a better idea of what you'd like to achieve. It might be that you're just looking to varnish the bare timber and not darken it at all with a stain. If that was the case, then the Cabot's exterior clear varnish might be what you're looking for.
The process will include sanding all the flat surfaces back first and then the inlaid sections by hand or with a detail sander. Once you're back to raw timber, you'll be able to follow this guide.