Gfilui

I want the terminal to show some kind of process bar based on time, like 1% every 60 seconds for example.

Create a progress bar in bash lists approaches to get a progress bar, so I'll concentrate on the How to fake part here. I'll use 2 seconds instead of your 60 here just for testing, adjust the sleep value to your exact needs.

Using dialog, whiptail or zenity (GUI)

for i in 1..100; do sleep 2; echo $i; done | dialog --gauge 'Running...' 6 60 0

This for loop loops¹ over the numbers one to hundred and echos them every 2 seconds, the output is then piped to dialog, which shows the number as the progress on a progress bar. This approach works for whiptail and zenity --progress (GUI) as well. dialog's output looks like this with a colored progress bar using 'curses' in text mode:

Using pv

for i in 1..100; do sleep 2; echo; done | pv -pWs100 >/dev/null

This loop is very similar, just that it prints only a newline (=1 byte of data) every 2 seconds, pv is then told to expect exactly 100 bytes of data and show a progress bar. In a terminal window with a width of 80 characters the output looks like this:

[===============> ] 22%

Constructing your own progress bar

With a simple loop you can also construct your own progress bar. Here are some examples that just print 100 # in one line, one per 2 seconds:

# number signs only
$ for i in 1..100; do sleep 2; echo -n #; done; echo
####################################################################################################

# with progress in % on the right
$ for i in 1..100; do sleep 2; printf "%0.s#" $(seq 1 $i); printf "%0.s " $(seq $i 100); printf "%3d%%r" "$i"; done; echo
###################################################### 54%

# with progress in % on the left
$ for i in 1..100; do sleep 2; printf "%3d%% " "$i"; printf "%0.s#" $(seq 1 $i); printf "%0.s " $(seq $i 100); printf "r"; done; echo
 39% ####################################### 

^{1 Look, a Polyptoton!}

Fake Progress Bar

Here's my fake progress bar:

It uses yad which is a super-charged version of zenity the default GUI used in the terminal. To install yad use:

sudo apt install yad

Here's the code you can copy and paste because everyone has the /usr/bin directory:

#!/bin/bash

# NAME: yad-progress-bar
# PATH: $HOME/bin
# DESC: Display yad progress bar % with names.
# DATE: Apr 23, 2018.

title="AU question: https://askubuntu.com/q/1027543/307523"
Percent=0 

for f in /usr/bin/* ; do # 1000+ files so this is fake loop
 echo "#$f" # Display file name in progress bar.
 echo $Percent # Percent complete
 Percent=$(( $Percent + 1 ))
 [[ $Percent -gt 100 ]] && break
 sleep .05 # Change to 2 seconds for OP's fake.

done | yad --progress --auto-close 
 --width=500 --height=300 
 --title="$title" --enable-log "Current filename" 
 --log-expanded --log-height=250 
 --log-on-top --percentage=0 
 --no-cancel --center

exit 0

The percentage is incremented by 1 in each iteration of the for loop. It should be calculating percentage on 1,000+ files but stops after 100 files.