Goal:
i want all my mobile client connect trough VLAN1 and access the internet freely.
Info :
i set up vlan1 for ehter1 as below :
/interface vlan add vlan-id=1 name=vlan1 interface=ether1 ( ether1 address = 192.168.1.1/24 )
/ip address add address=192.168.100.1/24 interface=vlan1
PPPoE has been setup on eher1 with the range of 192.168.88.0/24
i have masqueraded 192.168.88.0/24 and 192.168.100.0/24.
Issue :
i linked an access point to ether1 and enabled DHCP server and DNS on it :
DHCP : 192.168.100.10-192.168.100.254 ( this is the range of VLAN1 )
DNS : 8.8.8.8,4.2.2.4
now any mobile client will connect to this ap and can get an IP but cant connect to INTERNET
but all PPPoE user have the Internet
What is wrong ?

Have you enabled vlans on your switch at all or not.
Normally you would create two vlans on ether1 for example vlan 1 for wired clients and vlan 2 for wireless clients.
Create both vlans on the switch and create a trunk port (a port with 802.1q encapsulation) towards the router.
Create access-ports in vlan 1 on the switch to wired clients
Create access-ports in vlan 2 on the switch to the AP
having an ip on the ethernetport and a vlan over it is a bit strange setup although it might work but it is not common practice to do so I think.