Upgrading 955

Does Epix has watch faces which open that app if I click on it . Click on weather and it opens weather .

How long Garmin supports their watches as this is a year old Watch . Hoping they don’t have Gen 3 this year .

yes it does (as long as it's the garmin build in face) - there is possibility this will also be impleneted into 3rd party watch faces.

it also allowas to scrool back in the HR, barometer etc graph back in time (on the watch)

not sure how long it supports them, but fenix 6 was released in 2019 - and there is still new software released for it - including beta versions. - so that is now 3years  and a bit

I find that Garmin's estimates are pretty accurate in that with brightness set to 1/3, DND & battery saver (edited for OHR on) during sleep & brightness set to 1/4 (special option only for sleep), timeout 8 s, 7hrs GPS tracking  per week (using all instead of multi as tracks are excellent) every day, pluse ox off, using garmin watch faces I am getting between 5-6 days with AOD on and around 14-16 days with AOD off and wrist gesture on. Some of my activities are AOD on and some are AOD off (so a mixture during the week). Generally use AOD off and generally between 45-55% every monday when I recharge (percentage change depends on whether more or less I track.

Differences - assuming you spring for the sapphire Epix there really isn't that much between them, and sapphire with nylon strap brings you in line with FR955 weight. From software there are some minor differences with power management probably epix's biggest benefit, but also has slightly more options in regards to navigation and golf, plus believe its map use is much better (can double tap to zoom in, can long press to select waypoint etc) plus due to resolution maps are slightly more detailed. There are a couple of things the FR955 has but think the epix may already have got them or will be getting them, plus side benefit is it tends to get new features sooner and more likely to receive them too.  https://buy.garmin.com/en-GB/GB/catalog/product/compareResult.ep?compareProduct=777655&compareProduct=760778

Functionally (today!) there is very little difference between the 955 and Epix (or fenix 7). Although the soon-to-be-released ECG will certainly not make it to 955 (because metal vs polymer case). Looks like some minor golfing and expedition features are different https://buy.garmin.com/en-US/US/catalog/product/compareResult.ep?compareProduct=777655&compareProduct=760778

I get 5 days battery with AOD and daily hour workouts with GPS/music. Yes: the stock garmin faces have touch-to-open glances. And the (coming soon) Connect IQ 6 extends this to support 3rd party watch faces.

Is Epix comfortable to wear while workouts cardio , weights and sleep tracking .

955 is light and band is also comfortable to wear .

put on a nylon hook and loop strap - brings the sapphire version down to 50/51g.

Never had an issue wearing it for any activity including sleeping.

I did the swith last year in Nov, having FR955 right from when it was relesead. I have all the functions with very much similar time on battery. The display is huge delta to FR955 in favor of EPIX of course. 
I have like 12d with FR955 and I have like 9-10d with EPIX.

9 day is good with AMOLED screen to track all the activities.

Does Epix has move bar built in or it tells to move 

Yes Epix has move bar and it will give notifications if you don't move - can turn this on/off.

Currently not found a garmin watch face that offers the move bar as a data field on the watch face, but there are quite a few 3rd party options that do.

However as move bar is also shown under your today's step count in the steps widget, if you have a step watch face data point its easy enough to long press it, which takes you straight into the widget so can always see move bar with one long press.... on your watch face.